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We tested 25 backpacking water filters and treatment systems from Platypus, Sawyer, Katadyn, LifeStraw, and others to find the best option for your backcountry adventures.
Credit: Trish Matheny
By Amber King ⋅ Review Editor ⋅ Updated November 13, 2025
Clean water: You need it, and we want to ensure you have it, wherever you go. Bacteria, viruses, protozoa, microplastics, and more can be found in your drinking water if you're not careful.
We purchased and tested each filter on treks in Peru, expeditions across the USA, and even thru-hiked Iceland. We evaluated each filter's portability, the maintenance required to keep it operational in the field, and critical aspects of the model's design, including the types of contaminants it removes from water and the time it takes to process one liter of potable water.
For a backpacking party of one or for day trips, the LifeStraw Peak Squeeze is our favorite filter. This fast and lightweight filtration system produces some of the highest-quality water in our testing. However, if you're out with a group of friends, you will need something with a little more volume. In that case, the Platypus GravityWorks is a great option with a 4-liter capacity and a relatively fast filter rate.
Editor's Note: On November 13, 2025, we added a new filter budget group filter: the Waterdrop. We also retested the Sawyer Squeeze and Katadyn BeFree, which both got great durability upgrades.
Are you going out for a long trail day in the hills? The LifeStraw Peak Squeeze is a personal-sized model featuring a high-flow microfilter in a collapsible, packable soft bottle. The 0.2-micron hollow-core membrane microfilter provides a suitable solution for shallow water sources. You can simply remove the microfilter from the soft bottle to drink directly from the stream. Or scoop water on the go and then drink straight from the packable bottle. It will filter as you drink, fueled by a soft squeeze and your guzzling force. The soft bottle top is compatible with other bottles, and the filter can be removed to carry water between sources. In the field, the microfilter and collapsible bottle roll up to the size of your palm and are easily packed inside the pouch of a running vest. While we sometimes receive durability complaints with soft bottle systems, tester Trish Matheny was pleasantly surprised, noting, “The Peak Squeeze corrects many of the durability complaints I have with other collapsible bottle filters I've used.” When committing to long-distance adventures in the backcountry, this reliable and durable filtration system will not let you down. Another soft bottle option that's even more durable is the Hydrapak Flux 1.5L. It also offers more capacity, which makes for a faster treatment time if speed is a priority.
Regular maintenance is required to reach and maintain an optimal flow rate. This makes sense, given the small size of the microfilter. A syringe assist is necessary to remove extra particles from the hollow fibers. However, our tester reports, “I found that after a few backflushes, the filter quickly returned to the faster flow rate.” We found it simple enough to keep it in top condition. Most want something lightweight, easy to use, and highly effective at producing tasty, clean water. That means we are left with many good things to say about the Peak Squeeze. Its projected lifespan is 2,000 liters, twice that of its closest competitors. It also boasts a durable soft bottle design that resists tears, rips, and punctures, so you can take it on backcountry adventures for years to come. If a zero-maintenance option is more your thing and you are less concerned about silty particles in your water, the Aquamira Water Treatment Drops are a highly portable, budget solution that may be more suitable. On the other hand, a classic handheld filter like the MSR Guardian Purifier delivers a much more thorough clean to your drinking water overall. It is a great option if you want to fill up several water bottles at once.
The Platypus GravityWorks is our favorite gravity-fed backpacking water filter we tested. It is fast, portable, and easy to use. Setup is effortless, and our testers love its 4-liter potable water capacity, finding it useful for solo trips or small groups. The kit comes equipped with two durable 4-liter bags (one labeled “clean” and one labeled "dirty") and a high-flow filter that is compatible with hydration bladders and water bottles. Additionally, the bags can be converted into a solar shower or handwashing station to complete your base camp. “I love that I can simply hang this filter up with dirty water, walk away, and enjoy filtered water within minutes,” one of our testers mentions. The effortless aspect is a significant draw for many users: no pumping, no squeezing, and minimal waiting. Thanks to its versatility and ability to make filtering water a breeze, we think its 11.5-ounce weight is worth carrying on most trips. Though when ounces matter most, we'd opt for a lighter model like the Sawyer Squeeze mentioned above.
This filter is great, but potential buyers should be aware that it will not treat viruses. If that gives you cause for concern, you may be better off with a model like the MSR Guardian Purifier. Although she admits this is a small detail, Amber King said, “I struggled a bit to close up the zip-top on the bags in cold weather.” Additionally, the hanging attachments don't seem as durable as other models, but we didn't encounter any durability issues during testing, even after several backcountry trips. Like any gravity system that uses an in-line filter, the flow rate will slow down when exposed to water containing high amounts of sediment and requires removal by flipping the filtration unit upside down. Yet, for a durable and easy-to-maintain gravity filter with a high flow rate, the Platypus GravityWorks is our top recommendation for friends and readers alike.
Some backflushing often required to maintain flow rate
SPECIFICATIONS
Measured Weight (entire kit)
7.9 oz
Filter Pore Size
0.1 microns
Number of Liters/Gallons per Lifetime
378,541 L / 100,000 gal
Filter Media or Active Ingredient
Hollow fiber
Type of Filter/Purifier
Squeeze, in-line, on-the-go
If you are backpacking in a small group, the Sawyer Squeeze is the Goldilocks of water filters. A heavier and more expensive gravity system is better for large groups. A filter bottle is better for hiking and solo backpacking. The Squeeze is just right for smaller groups. The great value comes not only from the relatively low upfront cost, but the high number of uses you get between filter changes. Sawyer offers a “lifetime guarantee” on the filter (not the bag or other parts). So, as long as Sawyer honors that, you will never have to replace this filter. Of the multiple Sawyer Squeeze systems, this one offers the fastest flow rate, filtering one liter of water in just 40 seconds in our tests. It's also very packable. You can use it as a squeeze filter with accompanying bags or in line with a hydration bladder. You can even attach it to the top of a compatible water bottle or drink directly from puddles with its complementary straw. Only a few other contenders offer this level of versatility and portability. The Sawyer Squeeze is our top choice for use by one to two people.
There are no significant drawbacks to the Squeeze, but it faces considerable competition. Some filter bottles are lighter and less expensive for day users and solo backpackers. We recommend packing the syringe for cleaning the Sawyer Squeeze to ensure an efficient flow rate; otherwise, the filter will clog, and the flow rate will decrease after just a few filtrations. Drawbacks aside, the Sawyer Squeeze is an excellent lightweight option for day trips and personal use, provided you don't forget all its moving parts.
Long incubation time to eliminate Cryptosporidium cysts
Doesn't remove particulates
Minor chemical taste
If you've got time to wait for your potable water, the Aquamira Water Treatment Drops is a lightweight and inexpensive travel system used by many thru-hikers. Treatment is simple: activate the substances, drop them into water, and let them sit. When given ample time, it kills the most bacteria of all the chemical treatment systems we tested, including cryptosporidium cysts, a notable ability not shared by other chemical treatments. When combined with a filtration system, these drops can be easily used anywhere in the world. Plus, they are inexpensive and incredibly packable. There is no need for field maintenance, and the drops inherently never clog, which is a bonus that increases their reliability. On this note, lead tester Amber King says, “I love that there are no maintenance or durability issues to worry about when on the trail. The worst thing I could imagine is that I might accidentally knock over a bottle while treating my water.” So, as long as you're careful where you place the open bottles, we think you'll be fine.
Sadly, chemical treatment doesn't filter out particulates. Therefore, we recommend carrying a pre-filter or a handkerchief to assist with that work. Or, select one of our many award winners that can filter particulates like the lightweight and easy-to-use Sawyer Squeeze. And while the manufacturer advertises a 15-minute treatment time, in reality, you have to wait much longer (four hours is recommended) to eliminate hard-shelled cryptosporidium cysts. Because they so thoroughly destroy almost every living thing in the water, our tester says, “I think this is a great option — I just have to remind myself to leave time to wait for sterilization.” The Aquamira Treatment Drops offer great value for a couple of trips into the backcountry, but if you're seeking longer-term value, consider opting for another system in our testing lineup. Please note that this will result in a higher upfront cost. Overall, the Aquamira drops are definitely our favorite chemical treatment for backcountry water due to their packable design and ease of use.
If you infrequently backpack or want to save every last drop of cash, the Waterdrop Filter Straw and Gravity Bag can be a great option. The first couple of uses we had with this filter were flawless: quick and easy filtration that our 3-year-old helper loved assisting with. The large collection bag minimizes the number of trips to and from your water source. A cap helps protect the input source. When working well, it filters water plenty fast.
The major downside to this bag is its inconsistency. After a few uses with sediment-free High Sierra water, the flow rate precipitously declined. GearLab co-founder Chris McNamara notes, “I was just about to say nobody ever needs to spend more than $50 for a group water filter. But then the clogs began, and I changed my tune.” We went through the recommended backflushing techniques and got the water flowing again. Until it slowed down again. This is not a total deal breaker, as the water still eventually filters, and you can set this aside to attend to other camp chores. That said, there is a key difference between this and the more expensive gravity bags. We also found the plastic clamp to be somewhat cheap and not particularly effective. It was difficult to pinch the tubing completely closed and equally challenging to undo it. All that said, this is a great value option, especially for infrequent backpackers.
The MSR Guardian Purifier stands out for its exceptional ability among hand pumps on the market to remove water-borne viruses and other pathogens. The filter's 0.02-micron pore size is impressively tiny compared to the standard size of .1-.2 microns in the Katadyn BeFree. The hollow fiber filter delivers pure potable water and requires only easy field maintenance to continue delivering year after year. It's built to last; it's tough, and it's strong. We've owned one for over seven years, and it's performed well during international travel and hiking in the backcountry. Tester Amber King went the extra mile: “I also drop-tested the filter from six feet over concrete, just to double-check.” Its flow rate is exceptional for a pump filter (about 37 seconds for one liter), while the backflush system makes it functional even in the sludgiest of stagnant or turbid water holes. The filter is resistant to freezing, making it a suitable option for trips in colder climates. It's also the only system that performed remarkably well in turbid water due to its built-in backflushing system. If you encounter water muddied with sediment, this is the filter for the job.
Our testers found the Guardian to be quite remarkable, although we understand it may not be for everyone. The initial investment is tremendous, and to be frank, most people won't want to invest that kind of money. If you're searching for a pump filter that will suffice in North America, you probably don't need this Cadillac of hand pumps; a normal hand pump like the Katadyn Hiker Pro is adequate. Also, the Guardian is big, adding weight and bulk to your pack. One tester comments, “I don't love how bulky the filter is, but I like that it doesn't have a lot of loose parts to keep track of.” So, if you require a water purifier for international travel or one that offers a backflush system for turbid water, this model provides reliability that's worth the initial investment.
Effective Against: Particulates, bacteria, protozoa | Weight: 16.2 oz
PROS
Easy setup
Large volume reservoir
Packable
Has a sediment catcher
CONS
Slower flow rate
Requires regular maintenance
The MSR AutoFlow XL is a gravity backpacking water filter designed for large groups and base camps. Tester Amber King mentions that one of her favorite perks is the weight-to-water capacity ratio. While it doesn't compare to single-user models like the LifeStraw Peak Squeeze, Amber says, “I love how I can easily pack it into cracks and crevices to keep the weight of my bag down.” Its large capacity can hold up to 10 liters of water, and its adaptable design fits various storage vessels, again making it a perfect option for group trips. Out of all the models tested, this is our favorite for filtering large amounts of water due to its minimal setup and the ability to leave it unattended while filtering. It also doubles as a handwash station or even a shower during the warmer seasons.
Even though we love this system, it has the slowest flow rate of all the gravity filters we tested. We found that consistent backflushes are necessary, particularly when dealing with turbid water. If you're looking for a similar gravity filter with a quicker treatment time, the Platypus GravityWorks might be more your speed. Or, if you want to check out a more affordable gravity filter, consider the LifeStraw Peak 3L. Additionally, to utilize the full capacity of the MSR AutoFlow XL, you may find that your site selection is limited by the availability of strong anchors from which to hang it. Bottom line: This filter is a good option for those requiring a gravity filter that can handle large quantities of water with minimal effort.
Effective Against: Particulates, bacteria, protozoa, viruses, chemicals, heavy metals | Weight: 19.4 oz
PROS
The best water quality
Easy use
Easy field maintenance
CONS
Super bulky design
Purifies only small amounts of water at once
Short comparative cartridge life
The Grayl Geopress quickly became one of our most used and favorite purification systems. It supersedes most systems we compared it to for varied reasons. Basic functions, such as collecting water, filtering it, and drinking it immediately from the bottle, are all accounted for. More importantly, the Geopress removes the most disgusting water contaminants that you might find. It's said to remove not only viruses but also heavy metals, plastics, pesticides, and more. Our water came out clear when we tested it in a heavily metal-polluted river in Ouray, CO. We believe no other system could purify this water as effectively, with most still leaving some detectable smell or discoloration behind. The bottle also proved incredibly durable and met our needs while traveling. Save yourself from buying tons of disposable water bottles during travel and get the Grayl Geopress instead. And while we don't recommend this system for backcountry travel, the LifeStraw Go 1L is the perfect bottle filtration system for those who simply want to enjoy clean water while on the go in the airport or during a short hike outside town.
Compared to similar models, this bottle is much easier to push down to force the water through the filter, especially with the handgrips along the side. Although we appreciate the function, this system is not our first choice for lightweight backcountry travel due to its bulky and heavy design. If you want something less bulky and more affordable, consider the LifeStraw. The Grayl Geopress's cartridge life is minimal, and refills are costly. Based on these downsides and our side-by-side test comparisons, we conclude that this system offers relatively low value for the price. However, for traveling abroad, this system provides peace of mind when collecting water from taps or other potentially polluted sources.
The two-chamber design of the Grayl GeoPress makes it simple and quick to filter water between the two.
Credit: Jon Oleson
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Gear testing is a tough job but somebody's gotta do it. Our latest testing season took us to Cochamó Valley in Southern Chile where the ample water supply and adventurous rock climbing provided ample testing opportunities in unique locations.
Credit: Trish Matheny
How We Tested
To test each product in this review, we take to the trails. We run, hike, and bike hundreds of remote miles with filters in tow, guzzling gallons of water filtered and purified from trailside sources. Using a systematic test plan, we assess each system's anatomy, dissect the pros and cons, and evaluate whether a system is reliable enough to earn our favor. Each product sees hands-on and in-field experience. We also perform rigorous indoor tests to determine minute differences between products. We specifically make sludgy water samples using fertilizers, soils, and other particulates to truly test how each filter and purifier performs. Our recommendations are based on experience in the field and home-based experiments that compare the performance of each product.
Our comprehensive testing spanned six testing metrics:
Water Quality (20% overall score weighting)
Durability and Maintenance (20% weighting)
Treatment Time (15% weighting)
Weight and Packability (15% weighting)
Ease of Setup (15% weighting)
Ease of Filtration (15% weighting)
Why Trust GearLab
Jessica Haist, Amber King, and Trish Matheny are seasoned gear testers (with over 25 years of collective experience) who love to explore in the backcountry. Both Jessica and Amber work in outdoor education. As educators, they spend lots of time in the woods, backpacking along trails and exploring remote locations. You can find Jessica playing at the local granite crags, sucking up rays of the sun, or riding trails on her mountain bike, and Amber is an avid ultrarunner and rock climber with years of outdoor education under her belt. Trish is a member of the Yosemite Search and Rescue Team, where she has ample opportunities to test water filters in the backcountry of the ever-popular Yosemite National Park. During her off-seasons, she loves to travel, often splitting her time between running ultra distances and climbing granite. Our testing team utilizes these filters throughout the year, with over a decade of cumulative experience testing these filters and purifiers.
Our team of testers has put each of these water filters through the wringer so that we can provide you with the best recommendations based on your specific needs.
Analysis and Test Results
With a focus on backcountry water filters, we selected a diverse range of options. If you are not sure what option is best for you, read our article [How to Select a Backpacking Water Filter and Treatment System]. While it may be challenging to compare different categories of water treatment products (for example, chemical treatment versus a hand pump), the metrics used to evaluate each filter provide helpful insights into which products excel in one area or another.
Worse Value
Better Value
What's the Best Value?
We have numerous value recommendations tailored to various use cases. Keep in mind that the filters are a big part of the cost. However often you need to replace a filter greatly affects the lifetime cost.
For personal and infrequent use, the LifeStraw Peak Squeeze, our Editor's Choice, is a great value. While you only get 500 gallons per filter, that is more than enough for the casual user.
If you are filtering a higher volume, the Sawyer Squeeze is one of our best values. Yes, the upfront cost is not cheap, but you get 100,000 gallons between filters. A lifetime of use for more people.
For groups, the best deal is the Waterdrop Filter Straw and Gravity Bag. It is a fraction of the cost of the higher-end bags and totally adequate if you can tolerate some flow rate de-bugging.
While purification tablets and liquids like the Potable Aqua Purification Tablets, Aquamira Water Treatment Drops, and Katadyn Micropur Purification Tablets have a low upfront cost, they offer less value per liter over time as they need to be replaced every 30 liters or so. They are the best value for infrequent use and save you a ton of weight.
When not clogged, the Waterdrop is fast, efficient and fun to use.
Credit: Chris McNamara
Water Quality
We look at what each backpacking water filter can remove, as well as the overall taste and odor of the water. We went to shallow puddles, smelly swamps, and contaminated streams to see what each filter could do. Those that remove everything, including heavy metals and pesticides, triumphed in this category.
Backpacking water filters and purifiers use technology to remove protozoa, bacteria, and other water-borne pathogens. Filters typically don't have a pore size that can remove viruses. Other categories are chemical tablets and UV light systems. Below, we outline the different types of systems and their capabilities.
The Grayl Geopress (left) does the best in our water quality tests. All other filters processed this soil sludge filled with pesticides and other chemicals and produced this yellow colored water (right). While the Geopress produced clear, clean water that we actually trusted to drink.
Credit: Amber King
Water Purifiers
Water purifiers are essential if you're traveling abroad or living in areas with high pollution levels. Water purifiers remove particulates, protists, and bacteria, but can also eliminate viruses from the water. For example, the MSR Guardian is a tried-and-tested hand pump that can do just that. It expunges smells from water and removes viruses, but it can't remove heavy metals or chemicals. If you're traveling internationally, it's a great companion to filter water from the sink or a local stream.
The Guardian Purifier is somewhat overkill for the alpine streams in the Sierra Nevada, but it's perfect for traveling in developing nations where water can be unclean.
Credit: Jessica Haist
The Grayl Geopress stands out above the rest, using push technology to scrub water of contaminants. We tested this system on a particularly contaminated stream in Ouray, Colorado, which runs yellow due to pollutants such as lead, arsenic, chromium, and iron oxides. The water smells acidic, and it is acidic. After using the Geopress, all these metals were removed, and the water's pH was neutralized. We drank it shortly after, experiencing no unusual tastes or side effects. We'd also take the MSR Guardian with us, but we'd be more careful about our water source. However, the MSR Guardian has a much longer lifespan and can process more water in bulk.
A look at the purified product, provided by one of our favorite purification systems. It is said to offer protection from heavy metals, particulates, viruses, and other living organisms. In our tests, it was the only one that would remove the yellow color of this polluted river.
Credit: Amber King
UV Light
UV light purifiers also effectively eliminate water pathogens. UV light like the SteriPEN Ultra can be put into a glass of liquid and swirled around to destroy pathogens that could cause an infection. The SteriPen is easy to use and features a long structure that you swish around in water to achieve purification. Although the SteriPen provides excellent water quality, it does not remove particulates, odors, or metals, which is why it doesn't score as high as other models.
The SteriPEN Ultra uses ultraviolet light to get rid of harmful microorganisms.
Credit: Jen Reynolds
Chemical Treatment
Although chemical treatments are effective, they all impart an off-flavor to the water and do not effectively filter out particulates. The Aquamira Water Treatment Drops are our favorite chemical treatment tested because they kill all organisms (with enough time). At the same time, the Potable Aqua Purification Tablets and MSR Aquatabs can destroy viruses, bacteria, and some protozoans, but not Cryptosporidium. If you want to add a backup to your emergency kit, check out the Katadyn Micropur Purification Tablets, which have a 5-year shelf life but a strong chemical flavor. The Aquamira Drops have the least “chemical” taste of all three options we tested. Try filtering the water through a buff or handkerchief before treating it to reduce sediment, if necessary.
Pouring the Aquamira drops into our water to kill anything that we'd be concerned about.
Credit: Amber King
Water Filtration Units
A backpacking water filter (not a purifier) can remove particulates, bacteria, and protozoans (such as Giardia and Cryptosporidium), but cannot remove viruses. The best filtration systems can remove chemicals, heavy metals, and odors using activated carbon embedded in the core of the media.
The Platypus GravityWorks hard at work, cleaning out super turbid water and turning it into delicious and drinkable water.
Credit: Amber King
Of the backpacking water filters we tested, the Katadyn Hiker Pro, Katadyn Hiker, and MSR MiniWorks EX offer protection from microorganisms and chemicals, such as pesticides, to improve the taste of the water. And if these larger, bulkier systems feel a little outdated for you and you're after a lightweight, simple, on-the-go solution, our testers love the LifeStraw Peak Squeeze and the Hydrapak Flux 1.5L. The Peak Squeeze is perfect for solo missions, while the Flux can support a party of two. While there are other collapsible bottle filtration systems, these two stand out for their simplicity and durability.
Our testing team was impressed with the water quality provided by the Hydrapak Flux 1.5L, offering peace of mind in remote locations.
Credit: Trish Matheny
Filters remove particulates based on size. Protozoans are larger than bacteria, and viruses are approximately 10 times smaller than bacteria. Cysts from Giardia and Cryptosporidium require a filter media with pores smaller than 0.2 microns. Purifiers that filter based on size require filter media with an absolute size of 0.02 microns (note the extra zero) to effectively filter out viruses. Dirt is much larger than all of these microorganisms.
A Note on Water Turbidity
Planning for water sources that are entirely saturated with silty sediment — referred to as highly turbid — may be useful. For example, the Colorado River, which has carved out popular backpacking locations like the Grand Canyon, is one of the most turbid rivers in the world. If you live nearby, you've likely seen it transform from a clear, greenish color to what resembles chocolate milk shortly after rainfall.
The highly turbid Colorado River is a place where you may want to pre-filter you water...even with the best filter out there.
Credit: Amber King
Most backpacking water filters and purification systems cannot deal with the amount of sediment and silt in water sources like this. The only system that held up in these conditions is the MSR Guardian Purifier, another reason it's one of our favorites. It utilizes an auto backflush that cleans the filter with every pump.
The Guardian self cleans with every stroke, sucking water in through one hose and the purged water back out the other.
Credit: Jessica Haist
If you plan to travel to areas with high turbidity, bring a gallon ziplock bag or a bag specifically designated for settling water. Scoop up the silty water and let it settle for a few minutes. Clearwater will remain at the top, with sediment falling to the bottom. Gradually pour the upper layers of water into your filtration device or filter from the top of the bag. This is an easy and cheap “pre-filtration” technique for these areas. Some gravity systems feature a “sediment collector” at the bottom, such as the MSR AutoFlow XL.
The space between the bottom of the bag and the intake provides a place for sediment to settle out. This is considered the “sediment trap” that works really well with turbid water.
Credit: Amber King
Durability and Maintenance
Reliable backpacking water filters are constructed with durable materials. You don't want to be without a filter simply because it gets dropped, and you don't want to spend hours maintaining it. Products that offer high-quality components and reliability with minimal durability issues are available.
The most durable and reliable products are those that undergo chemical treatments. Each comes in either jars or prepackaged packets that can be placed in a plastic bag. They have no moving parts, don't require maintenance, and don't expire. If you want 100% reliability, this is it. The Aquamira Treatment Drops are a favorite of ours. We strongly recommend carrying these as a backup system, especially when traveling in the backcountry for extended periods. There are numerous situations where filters can clog, parts may be lost, or things may not function properly. Carrying these treatment drops can mean the difference between life, death, or grave discomfort.
Gravity Filters
All of these systems have filters that require frequent maintenance and care, depending on the amount of sediment filtered from the water. The Platypus GravityWorks 4L and the MSR gravity systems use the same hollow fiber technology. It's essential to know that regular backflushes are required, which involves simply flipping the filter upside down and allowing water to run through it. Similarly, the LifeStraw Peak Gravity 3L must be flushed with clean water, using a syringe to draw clean water through the filter to remove clogs. Alternatively, the Katadyn Gravity BeFree 6L requires a rinse, which is hard to do with water that isn't clear of sediment in the first place. All systems are generally durable and easy to use; ensure you're willing to meet their maintenance requirements to maintain maximum efficiency.
Toby Swimmer hangs the Katadyn BeFree Gravity 6L from this cottonwood tree in Indian Creek. This filtration system is very easy to use and can be maintained in the field by removing and rinsing the filter.
Credit: Trish Matheny
Hand Pumps
These models are generally durable until they become clogged. The MSR Guardian is the most durable and maintenance-free backpacking water purification system we tested, and we'd trust it anywhere. It auto-cleans, even in turbid water, offering the best reliability among hand pumps. It can also be frozen, unlike any other hand pump system. The MSR MiniWorks EX is another reliable hand pump with a ceramic-carbon core that can be easily serviced. Unfortunately, it requires a lot of maintenance to keep it working well (lots of scrubbing), but it can be repaired in the field, which is a bonus.
A look at the ultra-reliable and easy to maintain MSR MiniWorks EX. While it doesn't win any awards, it is one of the easiest filters to service in the field.
Credit: Amber King
The Katadyn Hiker Pro and Katadyn Hiker models are extremely consistent in performance. Both use a glass fiber filter that needs to be replaced if it becomes completely clogged. Both can be serviced in the field, but be cautious not to continue pumping if performance decreases. Between the two, the Hiker Pro is better by a hair. It's more durable and performs a bit better overall. For minimal improvement, though, we tend to recommend the Hiker. These pump filters require less maintenance than the MSR MiniWorks EX. Katadyn also offers the Katadyn Pocket hand pumps, one of the most durable filters we tested. It is easy to clean in the field or at home by removing the ceramic filter and using scour pads to restore the filter to its original color.
We discovered that the Hiker Pro is a great choice when water sources are small and hard to reach.
Credit: Jessica Haist
The MSR Hyperflow Microfilter is the fastest-flowing pump filter we tested, but it also requires the most service. When the filter is clogged, it must be backflushed, requiring a complete system disassembly to return it to a functional state. So, while it is a durable unit, regular maintenance is necessary (backflushing every 8 liters with clear water, more with turbid water), which can be a pain.
A look at all the components for the HyperFlow. The whole system is quite durable, small, and lightweight.
Credit: Amber King
Squeeze Systems
Our testers can't say enough about the durability of the Hydrapak Flux 1.5L. The 100% BPA and PVC-free soft bottle is constructed from a thick and sturdy combination of abrasion-resistant TPU, welded seams, and dual-layer laminate that we couldn't get to fail, no matter how hard we tried. After several days of adventurous rock climbing through sharp chimneys and off-widths with the bottle attached to our harness, we could not get the soft bottle or bail handle to fail. While the durability sets this filter apart from other popular squeeze options, such as the Sawyer Squeeze, the ease of maintenance is another key selling point. Rather than carrying extra parts to backflush the filter, remove it from the soft bottle and swish it in clean water to remove any sediment and particulates. While this process is simple and effective, our testers didn't deem it necessary until they filtered water from a particularly turbid river that was raging with sediment after significant rainfall.
We climbed 3,000 feet of technical granite to the summit of Trinidad Norte in Cochamó Valley with the Flux attached to the back of our harness. The lightweight and durable design (more specifically the flexible plastic bail handle) never failed.
Credit: Paddy O'Mara
Another great squeeze bottle is the LifeStraw Peak Squeeze, which corrects our durability complaints about the Sawyer and Katadyn bottles. The overall versatility is top-notch, as you can drink directly from the source or via the bottle after it has been filled. If there's a distance between water sources, you can remove the filter and store the water in the 33.8-ounce bottle to drink along your route. Regular maintenance is crucial for maintaining optimal flow rate, and the projected lifespan of the filter is twice that of the Katadyn BeFree.
The LifeStraw Peak Squeeze corrects all complaints regarding squeeze systems with flimsy bottles that are prone to failure when you need them. We attached the Peak Squeeze to our harness during several rock climbs in this remote valley and noted only cosmetic abrasions to the exterior plastic.
Credit: Trish Matheny
The Katadyn BeFree is a notable option for lightweight missions, such as trail running. The filter itself offers some of the best flow and adaptability. Cleaning is easy; just swish it in clean water. You don't need to carry any extra parts, and clogging is not a common issue.
The BeFree uses a unique filter that can “self swish” clean.
Credit: Kenji Mowrey
On-the-Go Systems
The Sawyer Squeeze and LifeStraw are two options that we like. If you're seeking the most barebones option that doesn't require you to carry extra items, the LifeStraw is where it's at. It's light, easy to carry, and long enough to provide easy access to water sources. The Squeeze Mini and Micro are suitable options for on-the-go carry, but they require a syringe and straw adapter.
A look at the intake for the LifeStraw. While you can't clean this directly, you can blow the water back through if it gets clogged. Although not ideal, it works well enough.
Credit: Amber King
UV Light
This is one of the most unreliable systems simply because it needs a power source. Battery life can be tough to predict, especially in colder temperatures. For this reason, we do not recommend taking filters like the SteriPen along for filtration during extended trips into the backcountry. However, it would be a suitable option for travel or for regularly purifying municipal water sources.
Due to the battery life the Steripen requires, we do not recommend it for extended backcountry trips.
Credit: Jen Reynolds
Backcountry Field Maintenance
Although maintenance is always important in the backcountry, it is useful to consider which options are the easiest to clean up, as this adds value to the filter's overall reliability in the field. This is especially true for those making a significant decision to undertake a long backpacking trail hike, where the water filter will need to be used for weeks or even months.
Of all the options tested, the easiest units to clean in the field are those that can be simply backflushed, such as the Platypus GravityWorks 4L and MSR AutoFlow XL. When thoroughly clogged, some filters require a complete replacement, which isn't ideal in a remote space. The easiest to maintain, by far, is the MSR Guardian Purifier, which backflushes and cleans itself and has been hassle-free in our testing.
We were surprised how easy and fast the MSR Guardian was to pump with great water quality at the end.
Credit: Jessica Haist
Treatment Time
This metric considers the time it takes to collect water from the source and then filter it. To test this, we noted whether water filtration is instantaneous. If not, we performed three separate time trials and averaged the results to determine the average time to filter one liter. The fastest times received the highest scores.
Straw Filters
The fastest backpacking water filter systems are the straw filters that allow you to drink water directly from the source. Water flow is typically slower than that of alternative filter styles and is heavily influenced by the individual construction of the input, filter body, and straw or bite valve. We found the Lifestraw personal straw fairly laborious to use, although we appreciated its small profile and think it could certainly come in handy when traveling light.
Little puddles in granite pockets are a perfect place to get water while alpine climbing with the LifeStraw.
Credit: Jessica Haist
Squeeze Filters
These backpacking water filters utilize a collapsible bottle or pouch, providing a modest amount of water storage, ranging from one to one-and-a-half liters. The Sawyer products all demonstrate this adaptability, but our favorite is the LifeStraw Peak Squeeze for its fast-flow bite valve that delivers water quickly. This makes it a favorite among hikers, bikers, and runners because water collection takes no time, and treatment is instantaneous.
Credit: Trish Matheny
Of all the Sawyer products, the Sawyer Squeeze presented the best flow rate during our side-by-side tests. In squeeze mode, it can filter a liter of water in just 40 seconds. The Mini, the smallest of the group, took 2 minutes to filter a liter of water, with the Micro taking a bit longer. However, if you like Squeeze products and want an impressive flow rate, consider the LifeStraw Peak Squeeze, which can filter a liter of water in just 35 seconds. Please note that this requires more maintenance to achieve maximum flow throughout the filter's lifespan.
The LifeStraw Peak Squeeze features a simple, user-friendly design with a fast treatment time.
Credit: Trish Matheny
Pump Filters
We pumped over 40 liters of water and timed it to see how many strokes each filter required to complete the task and which ones were the fastest. The hands-down winner in this category is the MSR Hyperflow (27 seconds, 29 strokes per liter). It pumps out hoards of water super quickly. However, this model also slowed down the fastest while in use, significantly reducing its flow rate as the liters accumulated. The MSR Guardian placed second, filtering a liter in 37 seconds and maintaining performance even in the murkiest water.
The MSR Hyperflow is the fastest pump filter tested, treating one liter of water in just under 30 seconds. Jack the dog and our main tester are impressed with its performance.
Credit: Amber King
The Katadyn products and the MSR Guardian offered the most consistent performance in our testing overall and worked best in turbid conditions. After a significant rainstorm, the Katadyn Pocket performed well, producing clean, high-quality drinking water — but we had to be patient, as it only produced one liter per minute. In these tests, the MSR Hyperflow and MiniWorks EX required cleaning every approximately 4 liters. In our sludge tests, all the pump filters, except the MSR Guardian, required cleaning after processing every liter of sludge. Impressive.
The MSR Miniworks
Credit: Amber King
Gravity Filters
With comparable flow rates, gravity filters are nice because you conveniently don't have to pump or do anything once they are set up. They can process large quantities of water, making them highly useful for groups of all sizes. All of the gravity filters are relatively close in treatment time, but the clear winner is the LifeStraw Peak Gravity 3L with a treatment time of 30-34 seconds per liter. The Katadyn BeFree Gravity 6L is a close second, filtering one liter in 40 seconds. The Platypus GravityWorks 4L comes in third place, filtering one liter in 52 seconds.
While not demonstrating the most optimal flow rate, gravity is doing all the work.
Credit: Trish Matheny
While gravity filters are inherently rad because there's so little work involved, there are some stark differences in performance. Please note that flow rates will decrease with murkier or turbid water, just as if the filters are not properly maintained. Also, note that if you aren't in a rush, the difference in waiting passively for one or two minutes for a liter of water is often not a big deal.
Weight and Packability
Weight and packability are essential. If you're carrying less weight, long hikes can be more enjoyable. We weigh each system and assess its relative profile to assess this metric.. We tested them with hydration vests, backpacking backpacks, and day packs. Generally, lighter and easier-to-pack products scored better than bulkier options.
Of all the treatments available, chemical treatments are, by far, the lightest-weight tool for the job. They can be a terrific choice for planning a long thru-hike or big trail run. Out of the treatments we tested, the MSR Aquatabs, Potable Aqua Purification Tablets, and Katadyn Micropur Purification Tablets can be easily packed into a small bag without needing to carry the entire bottle, thereby reducing weight. The only drawback is that these can leave a chemical taste in the water (for most people). The Aquamira Treatment Drops can't be parsed out like the tablets, but some prefer them because they don't taste as bad as the tablet options.
Chemical drops and tablets, like the Katadyn Micropur Purification Tablets, are certainly lightweight and affordable, but use potentially harmful chemicals and require lots of treatment time.
Credit: Trish Matheny
The lightest filtration systems are on-the-go systems, such as the collapsible Katadyn BeFree 0.6L, the Lifestraw personal filter, and the LifeStraw Peak Squeeze. Of the gravity filters, the Katadyn BeFree Gravity 6L is the lightest and most packable (9.28 ounces). If you prefer a hand pump system, the lightest systems are the MSR Hyperflow (10.6 ounces) and the Katadyn Hiker Pro (13.2 ounces).
Collapsible bottles and straw systems are the lightest filtration options, besides the chemical treatment drops and tablets.
Ease of Setup
We assess ease of setup based on the number of steps each filter requires to begin filtering water and whether that setup feels intuitive. We also consider how easily accessible different water sources are.
The Grayl UltraPress comes set up and ready to go; however, we found it difficult to fill the 16.9-ounce bottle when collecting water from shallow bodies of water.
Shallow water sources make it difficult to collect enough water to fill our 16.9 oz. Grayl Ultrapress bottle.
Credit: Trish Matheny
The easiest setups are the ones that require little thought, few instructions, and easy access. The top models have no parts to carry around or steps to follow. On-the-go systems are the easiest here, and the basic Lifestraw is the best for this. Unlike other more complex on-the-go systems, this filter only requires you to find a puddle or an accessible water source and simply drink from it.
A lightweight personal filter that allows you to drink from virtually anywhere.
Credit: Jessica Haist
Purification tablets are also pretty simple. Those like the MSR Aquatabs, Potable Aqua Tablets, and Katadyn Micropur Tablets just require you to drop them in the water and wait. The Aquamira Drops are also pretty simple but with a steeper learning curve. These require you to follow a series of specific steps, where you must mix two solutions and wait for a specified amount of time. The timeframe depends on the contaminants you need to eliminate from the water.
After filling your bottle, dropping in the tablet, move your water to a dark environment, and wait 4 hours for the process to be complete.
Credit: Trish Matheny
Hand pumps are also relatively easy to set up and provide access to a wide range of water sources. The Katadyn Hiker Pro, Katadyn Hiker, and MSR MiniWorks EX are favorites because their intake can capture water from the smallest nooks and crannies. The MSR Guardian works well for this, but it has a larger particle screen that makes it harder to reach shallow sources. Pump filters excel at accessing water over steep banks, boat sides, or fast rivers when water access is an issue. While easy to pump, the Katadyn Pocket has many moving parts, and we felt it necessary to carefully read the instructions to ensure we had the input and output hoses in the correct locations.
The Katadyn Hiker allows you to take water easily from any source. Steep banks, shallow streams, babbling brooks. This is due to its weighted intake with a high quality prefilter.
Credit: Amber King
Gravity filters require more effort to set up because they need a place to be elevated. The ideal scenario is to hang the filter from a branch. If that is not available, you may need to get creative. Reservoirs with large openings and flexible designs can draw water from a wide range of sources. However, because you have to scoop up water, the source needs to have a sufficient pool to collect water. Shallow pools are harder to reach.
The LifeStraw Peak 3L provides a simple setup that is easy to use and also easy to clean thanks to a larger opening where the filter attaches to the soft storage bag. The webbing attachment is sturdy and the carry strap makes it easy to move the bag between the stream and your campsite.
Credit: Trish Matheny
Ease of Filtration
We examine the physical effort required to filter water through the backpacking water filtration system. While we don't score storage capacity, we note how much water each system is designed to store or whether an additional bottle is necessary for storage.
UV Purifiers
The SteriPen Ultra requires the least work of all the categories we tested. Setup is easy; simply turn the light on. Although the SteriPen takes less time to filter a liter than other UV options, it is not hands-free and requires consistent attention during the purification process.
The Steripen Ultra is not a hands free device, requiring consistent swirling and attention during water purification.
Credit: Jen Reynolds
Gravity Filters
Gravity backpacking water filters are the best systems for ease of filtration. After setting up, the filtration process is hands-free. All gravity filters in our review earn top points for being easy to filter. These filtration systems can quickly move large amounts of water, making them a top choice for groups. One difference is the height requirement to filter. Some need full suspension and can't be put on the ground. In contrast, the MSR AutoFlow and the Platypus GravityWorks can be laid on a hill or over a rock and still filter water.
Filtration with the Platypus Gravity doesn't require a huge height differential.
Credit: Amber King
Some come with “clean water” vessels like the Platypus GravityWorks while others like the Katadyn Gravity BeFree 6L and MSR AutoFlow have a simple hose running from the bag to a storage vessel of your choice. All adapt nicely with a hydration bladder and can be filtered into a bottle if needed.
Hand Pumps
Hand pumps are a bit more challenging to use, as you must physically pump to move water through the system. Hand filters vary in design and efficiency, which is determined by the output per pump. Of the hand pumps we tested, the MSR Hyperflow, MSR Guardian, and the Katadyn Pocket are the easiest to use. They are highly efficient filters, resulting in less pumping and increased water production. The Guardian has a large handle that's easy to grab, similar to the MSR MiniWorks EX. The MSR Hyperflow has a smaller system, but it is still quite ergonomic. The Katadyn Pocket has been recently redesigned with a new grip handle and a longer outlet hose to increase efficiency and provide maximum comfort as water flows through the system. Most hand pumps we tested have attachments that best fit a Nalgene bottle. The Katadyn Hiker models have easy-to-use handles but aren't as ergonomic as the MSR products.
We love the large handle on the MSR MiniWorks EX, though it's overall not the easiest to use.
Credit: Amber King
On-the-go Filters
On-the-go backpacking water filtration systems are typically easy to set up but are propelled by either sucking or squeezing forces. Of the on-the-go systems, the LifeStraw Peak Squeeze, the Hydrapak Flux 1.5L, and Sawyer Squeeze are the easiest to suck through when in straw style. Others are harder, like the Sawyer Mini, which gives you very little water for each suckle. Press action filters, such as the Grayl UltraPress, provide another on-the-go option, requiring only a little extra effort to press the water through the filter before enjoying the results immediately or storing it in the durable bottle for later use. And other bottle filter options, such as the LifeStraw Go 1L, were easy to use, as you simply fill the water bottle before drinking through an opening in the lid. Still, we found the bulkier and heavier option a little overkill for the backcountry.
On-the-go water filtration systems, like the Grayl Ultrapress, can be a convenient way to filter clean water from a variety of sources.
Credit: Trish Matheny
How to Select a Backpacking Water Filter and Treatment System For You
While there are many water filtration and purification options, it's useful to identify some key considerations before making a purchase.
We hope the short article below helps you select the best filtration option for your next adventure.
Credit: Trish Matheny
What Type of Water Filter or Purifier Do You Need?
Before diving into the specific types, it is important to decipher between water purification and filtration. Water filters strain harmful bacteria and protozoa through the filter, but do not remove viruses. In contrast, water purifiers are specifically designed to kill viruses.
Pump Filters
Pump filters typically treat water by hand-pumping water through the filter, which features a pore size small enough to prevent microorganisms from passing through. While it takes longer to pump the water by hand, they are reliable and perfect for one to two people.
Hand pumps require patience and strength but can be reliable for one to two people during backcountry objectives.
Credit: Amber King
Gravity Filters
Gravity filters treat water by allowing gravity to push water through the filter, thereby eliminating the time and effort required to pump by hand. Some gravity-fed filters are even interchangeable with other handheld options. Although they require a tree or something to hang the bag from for gravity to take effect, they are easy to use, offer ample storage, and are perfect for large groups and base camps.
Credit: Kenji Mowrey
On-The-Go Systems
On-the-go systems treat water through a straw placed directly into the water source, using the filter itself, or by attachment to a compatible bottle. Water is essentially filtered as you drink. These filters are often lightweight and super packable, making them the perfect choice for solo missions. The only downside is that water storage requires another bottle.
On-the-go filters are perfect for solo missions thanks to their lightweight versatility.
Credit: Trish Matheny
Bottle Filters
Bottle filters utilize a built-in filter inside the bottle, where you press the water through the filter before drinking. These personalized filtration systems can be difficult to press but are often perfect for solo front-country travel or short hikes in the wilderness.
Bottle filters are easy to use and perfect for one person.
Credit: Trish Matheny
Chemical Drops and Tablets
Chemical drops and tablets purify water by releasing chemicals that kill viruses, most protozoa, and bacteria. That being said, these are incapable of killing Cryptosporidium, which is common in North America. Therefore, these treatments are ideal when combined with another form of filtration. Ultimately, we recommend using these treatments in emergencies due to their long treatment time and terrible flavor.
Although very packable, we recommend using chemical drops and tablets only when absolutely necessary.
Credit: Trish Matheny
UV Light Purifiers
UV Light Purifiers are designed to purify water by destroying harmful viruses through contact with ultraviolet light. This process confuses the DNA of these tiny pathogens, which prevents them from reproducing; afterwards, the treated water is safe to consume. These purifiers are best suited for international travel but require battery life and aren't capable of removing particulates.
UV options utilize ultraviolet light to destroy microorganisms.
Credit: Jen Reynolds
What Will You Use Your Filter For?
There are many different ways to enjoy traveling in the great outdoors. If you plan on moving quickly through demanding terrain on solo missions, on-the-go filtration may be the perfect choice to drink directly from the stream. Backpacking with a family? Perhaps the simplicity and ease of a gravity-fed filter are the best choice for your base camp. No matter your activity, a filter is designed to meet your specific needs.
Whether you're setting out for an ultralight solo mission or backpacking with a group its important to consider your specific needs for water filtration.
Credit: Trish Matheny
Other Filters to Consider
Platypus QuickDraw Microfilter System - This is a light (3.6 oz) option with a relatively good flow rate. Its major downside is the short 1,000-liter lifespan of the filter cartridge. This makes it a relatively expensive long-term investment compared to the competition.
Katadyn Vario - This used to be the standard for producing high-quality filtered water. Now there is a lot of competition. While we still believe this is a suitable filter, it is expensive and heavy compared to other systems.
MSR Trailshot - When released, this was one of the more innovative and lightweight personal water filters. However, there are now many more versatile and inexpensive filter options that are lighter.
Conclusion
A critical gear consideration, such as a water filter or purifier, warrants thorough research and hands-on testing. Whether you are filtering water for a group or simply want to add a backup to your emergency kit, this is where we come in. We hope that our insights have helped you in your search and in narrowing down your options. Happy trails!
Having a solid lineup of camping gear you can trust makes all the difference when heading out into the backcountry. If you're in the market for a new backpack or packable stove, we have recommendations for your specific needs and budget. And being prepared with a backpacking gear checklist never hurts anyone.
We hope our testing perspectives and evaluations help you make the best water filter purchase for your next adventure.
