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From lightweight, minimalistic hydration packs to those with expandable storage, we've tested over 47 hydration packs since 2014 to help you find the best one for your outdoor pursuits. Our expert testers hiked and biked hundreds of miles with these packs throughout Arizona, Minnesota, and Utah, putting them through extensive hands-on, real-world testing. Our team takes extensive notes on each pack's performance, evaluating its strengths and weaknesses in five performance metrics: hydration system quality, storage volume, and comfort. No matter where your outdoor pursuits take you, we'll help you find the best pack to help you stay hydrated.
Breathability, excellent storage, comfort and support
Tons of storage, comfortable, supportive, versatile
Good storage, easy to access bladder, hip belt pockets, comfortable bite valve, lightweight
Excellent storage and organization, breathable back panel, adjustable hip belt
Big volume, lightweight, great price
Lightweight, large storage volume, solid hydration system
Large storage capacity, breathable, good flow rate bite valve
Easy-to-access pockets, minimal movement during activity, lightweight,
good storage
Excellent drinking hose design, comfortable straps and hip belt, lightweight
Lightweight, creative storage, uncomplicated
Easy to use on/off tab on bite valve, lightweight
Lots of storage, adjustable fit for a range of body sizes
Cons
Expensive, thin hip belt
Bite valve is hard to drink from, heavy, putting a full bladder back into its pocket can be difficult
No rain cover, only comes with 2-liter bladder
Heavy, expensive
Fewer pockets, lacking breathability
Limited organization, poor back panel ventilation
Bladder is hard to access, bite valve magnet is fickle
Pressure across the chest from straps, does not fit all body shapes and sizes
Less storage than others, tedious reservoir placement
Minimal storage, shoulder straps are snug for users with broad shoulders or larger torsos, shoulder straps can easily twist when putting the pack on
Straps lack adjustability, a full bladder is difficult to get into the pack, straps and clip are uncomfortable for people with breasts
Bite valve is hard to use, bladder is hard to clean, bladder is hard to fill
Bottom Line
This comfortable, breathable, supportive, and full-featured hydration pack earns our highest praise
A versatile pack with loads of storage and a great choice for all-day adventures on the trails
It's hard to find many faults with this well thought out pack that has a great blend of storage capacity and comfort
A comfortable, high-performing pack with plenty of volume and nearly every available storage feature
A simple bag with a functional design and an excellent volume to weight to price ratio
An all-around pack that successfully blurs the line between hydration pack and daypack
This mid-volume pack has a super breathable back panel, ample storage, and a 3-liter bladder making it a great choice for all-day adventures
With 8 liters of storage, including easy to access pockets on the shoulder straps and a 2 liter reservoir, this pack is a great pick for saving weight without sacrificing storage
A sleek and lightweight pack that features an innovative drinking hose design
A minimalist, lightweight pack with a highly rated hydration system for those looking to be able to stash a layer and carry the basics
This minimalistic pack lacks adjustment in the upper part of the shoulder straps, making it difficult to achieve a comfortable fit for some people
This pack’s highlight is its storage space, but its hydration system is hard to use and difficult to clean
We loved the Osprey Syncro 12 right off the bat, which was only confirmed by our testing as this pack rose to the top across many of our test metrics. It has a versatile design, quality construction, and a thoughtful storage and organization layout. The back panel is breathable and comfortable and the hydration system is top-notch. We love the well-placed drinking hose release clip that makes filling and replacing the bladder a breeze, and the storage layout includes both well-placed pockets and plenty of overall volume for bulkier items like a jacket or sweatshirt. This pack doesn't show any significant weaknesses and exhibits the quality we've come to expect from Osprey products. One tester has been using this pack consistently for over a year without any noticeable wear or tear.
While the Syncro 12 is an all-around capable option, it's not lightweight. Its quality construction and many features land it among our lineup's heaviest packs. A comfortable carrying system compensates for this, but there are probably better and lower-profile options for fast and light pursuits. We also appreciate designs with zippered hip belt pockets, one of the only high-end features notably absent from this model. Overall, the Syncro earns our highest honor and a strong recommendation for its impressive job balancing storage volume, organization, carrying comfort, and hydration performance. If you're looking for something lighter-weight (and lighter on the wallet), check out the minimalist CamelBak Classic Light 70.
The Syncro is a great choice for mountain biking and hiking. With side and front storage pockets, you can add a water bottle and quickly stow extra layers.
The Gregory Nano 18 H2O earns recognition for its excellent value, offering ample storage volume and low weight at a surprisingly low price tag. This awesome pack has one of the larger storage volumes (18 liters) and water capacities (3 liters) in this category while still managing to boast one of the lowest weights and price tags. The simple, straightforward design makes it easy to carry bulkier items in the primary storage compartment and keep smaller items organized in the exterior zippered pocket on the top lid. The hydration system is painless to use and take in and out of the pack.
However, the Nano 18 H2O sacrifices many of the premium features found on some of the pricier packs. Considering it's one of the most affordable packs we tested, it's certainly comfortable, though the padded back panel is not as breathable as other models with open mesh panels, potentially leading to a hot, sweaty back. And while the large main storage compartment is great for stashing bulkier items, it doesn't have the detailed organization and storage capabilities found on other packs with multiple interior pockets, like the Gregory Endo 15L. The Gregory Nano 18 outperforms many packs with higher price tags, though it lacks some higher-end features. Nonetheless, we find it's an impressive bang for the buck.
The USWE Rush 8L is a great option for those who dislike bulky packs or are looking for a lightweight, stowable option to more rigid packs. Weighing a svelte 19.2 ounces, this hydration vest's 8 liter capacity features a 2 liter bladder with five strategically placed storage pockets, three of which are on the shoulder straps and are easy to access during activity. While this pack is billed as a mountain bike pack, it was a great pack for shorter hikes and would even be worthy of consideration as an alternative to a top choice from our best hydration pack for running review. The main compartment has a storage area and a sleeve for the reservoir. We were impressed at how much the storage area could hold, including a light jacket and a small first aid kit. The low back of the pack features a mesh storage pocket, which is a great place to stow additional essentials, such as bulkier snacks, tools, and sunscreen. The pack hugs the body, preventing too much jostling during activity. An elastic shock cord strap is found on both the left and right side of the vest under the armpits to adjust the fit across the chest, and two straps feed from the shoulder straps into the No Bounce Compression Compartment (NBCC). As you drain the bladder, you can tighten these straps to prevent the pack from moving around on your back.
The pack is comfortable to wear, depending on your build. Our tester's biggest gripe with the Rush 8L is its straps. There is no shoulder strap adjustment. Instead, you make adjustments using shock cords on the sides of the pack; this can make getting the vest on and off tricky, depending on your shoulder flexibility and what you are wearing. The vest clung to fleece versus slipperier materials. Our testers were also very aware of the straps while wearing the pack. Despite the mesh straps, the pack feels warm during activity. A size medium pack fits our primary female tester comfortably. Still, other female testers whose measurements fell within the size range for a medium could not wear the pack because it was too tight across the chest. We highly recommend measuring yourself and, if you're in between sizes, to size up for greater comfort. If the Rush 8L strap design is a deterrent, we recommend checking out the CamelBak Classic Light 70, which features traditional shoulder straps and an adjustable sternum strap. You might also consider the Ultimate Direction Ultra Vest 6.0 if you prefer soft bottles on the chest instead of a hydration bladder.
The USWE Rush 8L Hydration Vest stays put while hiking and is very lightweight.
The redesigned Deuter Compact EXP 14 earns top marks for its smart storage and versatility. This 14-liter pack has lots of storage and pockets to keep things organized and expands to 19 liters, making it a great choice for all-day adventures. Our testers are impressed with how supportive this pack is and how well it carries heavy loads. Features like a 3-liter bladder, pockets on the hip belt, a rain cover, integrated helmet storage, and mesh side pockets add to this pack's value and versatility. This pack proved comfortable and stable on mountain bike rides and hikes, and could even be used for snowsports.
The biggest drawback to the Compact EXP 14 is its weight — all of those pockets and features add up, and this pack tips the scales at a whopping 41.6 ounces. The side-load bladder can be a bit challenging to get back into its pocket when the pack is full, and while the bite valve is not the easiest to drink from, it is well-constructed and has a cover. Overall, this pack is a great choice for those needing extra gear storage, and it earns high marks for its storage and comfort. If you need an option for going fast and light, check out the CamelBak Classic Light 70.
The Gregory Endo 15 is recognized for its outstanding storage and organization, boasting a large 3-liter 3D-Hydro water reservoir, a comfortable and adjustable suspension system, and a pocket or sleeve for every piece of gear. In addition to a large main storage compartment that houses the water reservoir and a removable tool pouch, this pack includes a front zippered compartment with a padded and lined sunglasses pocket, an external zippered valuables pocket, and zippered hip belt pockets. A ventilated back panel supports the cleverly designed storage features with moisture-wicking mesh and an adjustable Shift RS hip belt to help dial in a comfortable custom fit.
While the high-end features on this pack are undoubtedly impressive, they come with a weight penalty, making the Endo 15 one of the heaviest packs in our lineup. And although the 3-liter reservoir provides plenty of capacity, it's a little bit trickier to access and remove than models with a separate reservoir sleeve, and its smaller circular opening makes refilling and cleaning more complicated than with some of the other top-rated hydration systems. However, the Endo 15 makes a great choice for a heavy-duty hauler to help organize hiking gear, bike tools, camping equipment, or tools for fieldwork. For a lighter weight and lower profile pack with a bladder that's easier to clean, we recommend the Evoc Ride 12L.
With its revolutionary ReTrakt drinking hose return system, the Thule Vital 6 made a significant impression on our testers. While every other top model has a hose clip or magnetic bite valve attachment, nothing else comes close to this design's simplicity and performance. The drinking bite valve is conveniently housed along the right shoulder strap with a long, flexible magnetic strip, making it easy to grasp and reliably and securely returns when you release it. The Vital also provides a secure, comfortable fit without bouncing or flopping around with its lightweight pack design, low center of gravity, and wide hip belt and shoulder straps.
While we were uniquely impressed by the drinking hose return system outside the pack, we were a little underwhelmed with the reservoir housing inside the bag. The hanger loop and T-shaped reservoir hook are more tedious to work with than most other designs, making removing and replacing the reservoir for refilling or cleaning a bit more challenging. The 6-liter storage volume is on the smaller side but is an ideal design for a day out on the bike and has enough room to pack a jacket and all of your essential gear. Overall, the Thule Vital is excellent for anyone who loves the convenience of a hydration bladder but is tired of the drinking hose always flopping around. If you need a bit more storage space but still want a lower-profile pack, we recommend the Evoc Ride 12L.
For those who want an affordable, top-of-the-line hydration system without the need for extra storage or complicated features, the redesigned CamelBak Classic Light is an optimal choice. This pack is lightweight with a consistently reliable and easy-to-use hydration system, and it also has creative storage solutions that make it more versatile than previous iterations. A large front pocket is large enough to hold a wallet, keys, phone, snacks, and other small items, while side bungee straps allow you to stow a jacket or heavier layer, making this a great choice for the lightweight crowd.
The hydration system is easy to use, and the reservoir has a large handle that makes filling it even easier. While not the easiest-to-clean reservoir, the screw-top opening is large enough to easily accommodate a cleaning brush. For cyclists, there are two small pieces of webbing to thread a helmet through that act as a helmet carry and a tab to clip a light onto at the base of the pack. If you're someone who appreciates a well-designed, lightweight pack without a lot of frills, the CamelBak Classic Light is hard to beat and has an attractive price. Minimalists may also like the sleek Thule Vital 6L, which has a great magnetic hose system.
The minimalist CamelBak Light has some great storage features and a reliable and easy to use hydration system.
Credit: Tara Reddinger-Adams
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We tested hydration packs for years on the hiking and mountain bike trails to bring you the best available options.
Credit: Tara Reddinger-Adams
How We Test Hydration Packs
Our team has mountain biked and hiked California's coastal redwoods, Arizona's desert landscapes, and the Land of 10,000 Lakes, Minnesota, with these hydration packs. To begin our testing, we familiarized ourselves with each pack and its storage and hydration system. We then filled the pack with items we would carry on the trail and more to determine its capacity. We filled the reservoir, inserted them into the pack, routed the hoses, and headed out onto the trails. We drank from each pack as we hiked and biked while keeping notes on each pack's performance. We recruited other hikers and riders to use the packs and provide feedback on what they did or didn't like and why. Each hydration system was disassembled, cleaned, and put back together. We test each hydration pack based on metrics including drinking, filling, cleaning, comfort and storage capabilities, and overall weight.
Our test metrics for hydration packs include:
• Ease of Drinking (20% of score weighting)
• Ease of Filling (20% of score)
• Comfort (20% of score)
• Storage (20% of score)
• Weight (10% of score)
• Ease of Cleaning (10% of score)
Why Trust GearLab
To test hydration packs, we enlisted the expertise of gear testers Tara Reddinger-Adams, Nick Bruckbauer, and Jason Cronk. As experienced hikers, bikers, and all-around outdoors people, this group understands the importance of quality gear and efficient hydration. Tara has been testing for GearLab for nearly five years and calls Arizona home. She worked in the bike industry for 11 years and was a certified mountain bike coach and guide for over six years. She relies on gear that performs well on the trails, appreciates features that add functionality, and always listens to people's needs before making gear recommendations. You'll find her exploring on foot or on her mountain bike in search of new trails. Nick and Jason are longtime GearLab contributors and residents of the beautiful Lake Tahoe area, where they can be found shredding the trails all year via foot, bike, or skis.
How To Choose a Hydration Pack
We've put together four important buying considerations, including size, features, and water capacity, to help find the right pack to keep you hydrated and comfortable on your next adventure.
What's Your Intended Use?
Hydration packs come in various sizes and can be activity-specific. Day-hiking packs are designed to distribute loads comfortably and may include activity-specific features such as straps for carrying trekking poles. Mountain bike-specific packs generally have compartmentalized storage for tools, pumps, and more. Running packs are designed to minimize bounce and allow easy access to food thanks to pockets on the shoulder straps. When choosing a hydration pack, consider your typical activities and how you'll use the pack. Choosing a pack that aligns with your activities will ensure your pack fits properly and has the necessary features for your adventures. And remember, just because a pack is designed for one type of activity does not prevent it from being used for another.
How Much Water Do You Need?
It's important to consider how much water you need on a given day. If you typically go on shorter hikes or rides, a 1.5-liter reservoir can work well but may be limiting for longer activities or in hotter climates, where a 3-liter reservoir is preferable. If you'd prefer to get more versatility out of your pack, you can always partially fill your bladder, but typically, a larger bladder means carrying a larger volume pack. When buying your next hydration pack, consider your typical water intake and the tradeoff between extra water or a lighter pack. Some packs have side pockets large enough to stow a water bottle for increased hydration needs.
Knowing how long you'll be out and how much water and gear you need to carry is an important part of the decision-making process when buying a hydration pack.
How Much Gear Do You Carry?
Hydration packs come in sizes ranging from 2 liters upwards of 50 liters. Deciding on the right size pack will also depend on your activities and time spent on the trail. Smaller packs are great for traveling light or for carrying minimal stuff like a light layer and some energy bars. On longer rides, hikes, or overnight trips, a larger pack is necessary to carry extra layers, food, and emergency items. To decide on the right pack size, consider your must-have items and any extra gear you think would benefit your activity of choice.
Some packs are designed to carry water and not much else. This one has a small pocket inside that is large enough to put a small energy bar in or keys.
Credit: Tara Reddinger-Adams
What to Look for in a Comfortable Pack
Being miles away from the trailhead with a sore back and shoulders is a situation no one wants to find themselves in. Finding a comfortable pack means taking into consideration your torso shape and size. Some packs feature adjustable shoulder straps, while others may not. Padding in the shoulder straps can improve comfort, as can wider hip belts. Also, consider if the pack has a support system, such as a wireframe, to help support larger weight loads. Ventilation is also important, especially in hot climates, so keep an eye out for packs with mesh backing or ones designed to sit away from your back.
Back panels that have a frame or channel that create space between the pack and your back allow for more airflow and feel cooler.
Credit: Tara Reddinger-Adams
Analysis and Test Results
We researched and analyzed the top hydration packs on the market and purchased carefully selected models from well-known and up-and-coming manufacturers. All the packs in our review come with a hydration bladder, drinking hose, hose routing system, and bite valve. While packs may look similar at first glance, differences in both the pack's and hydration systems' design affect their overall performance, such as how comfortable the pack is, the bite valve's ease of drinking, a reservoir's ease of cleaning, or how easy the reservoir is to fill. To help you identify which models excel and in what areas, we analyzed each backpack and hydration system design across six rating metrics.
What's the Best Value?
We do not factor price into a product's scoring but recognize that individual budgets vary and a product's value includes its price and performance. Products that cost less can sometimes perform just as well (or nearly as well) as those that are more expensive. We also realize that not everyone needs (or wants) every possible feature and that sometimes less is more, both literally and figuratively. We have compared both price and overall performance for each hydration pack tested to highlight each pack's performance features.
The hydration packs in our review all come with a hydration system and a backpack, which generally offer cost savings compared to purchasing each component separately. Some daypacks of similar size cost as much as the options in this review but don't include a hydration bladder. The Gregory Nano 18 H2O provides a 3-liter reservoir with a large storage volume and outstanding comfort at almost half the price of some high-end models. In contrast, the CamelBak Classic Light provides a top-notch hydration system in a minimalist pack design at a lower price.
The Classic Light is not only a great value it also has a tried and true hydration system and is a great choice for when you don't need to carry much.
Credit: Byron Adams
Ease of Drinking
Since hydration is the primary purpose of a hydration pack, we focus our testing on the drinking performance of each pack's hydration system. We analyze each system's flow rate, ease of drinking, and how well the system integrates with the pack. Some packs have straps to help route the hose along the shoulder strap, while others feature a clip magnet to hold the hose in place and prevent it from bouncing around. Many packs also have a clip or strap that the reservoir hangs on inside the pack; this prevents the bladder from falling to the bottom of the pack and becoming crumpled as you drink from it. For this metric, we also consider the overall bladder volume and how easily we could drink from the bite valve.
The differences between how easily each model delivers the water became apparent during our testing, and we started narrowing down each brand's performance. We found CamelBak products are some of the easiest to drink from with their Big Bite valves, which deliver a flow of water that allows for easy drinking, while other bite valves require you to suck on them to get water. HydraPak hydration systems, such as those on Evoc packs and USWE Rush 8L, have a circular shape bite valve that is easy to drink from and provides a good amount of water.
Some bite valve designs have a shut-off valve. This valve prevents water flow to the bite valve from the hose and is handy when transporting your pack by preventing accidental leaks. CamelBak's Crux Reservoir and the HydraPak reservoir found on the USWE Outlander Pro 2L pack both feature an on/off switch that flips and is easy to operate with one hand, even with gloves on. This feature is also useful when you tear a hole in the silicone part of a bite valve, and it begins to drip since you can easily turn off the water flow. In contrast, the bite valves on the Deuter Streamer reservoir, Osprey Hydraulics reservoir, and the USWE Rush 8L Hydration Vest's HydraPak reservoir close by twisting the bite value. This process generally requires two hands and is more difficult to do while moving on the bike. In general, shut-off valves that only need one hand to operate are preferred.
On the left is a twist-close bite valve versus a flip switch on the right. In general, the flip switch on/off bite valves are easier to operate.
Credit: Tara Reddinger-Adams
The hydration system's overall design can greatly influence your drinking. Poorly routed hoses that kink or bite valves with a low flow rate can be frustrating. The same is true of having a bladder that is too small and running out of water. Here, packs with larger water reservoir volumes and better drinking hose attachment systems score higher. The Thule Vital 6 stands out with its innovative ReTrakt drinking hose return system that keeps the bite valve secure and easily accessible.
Thule's ReTrakt drinking hose has a flexible magnetic strip to keep the hose secured to the pack's strap. We loved this system and favored it above all others.
Credit: Nick Bruckbauer
Ease of Filling
Filling a reservoir and fitting it back into the pack can be a chore, especially when the reservoir is difficult to use, or the hose needs to be rerouted through the shoulder strap. Luckily, many hydration systems have integrated quick-connect hoses. This button is located at a mid-point on the hose or where the hose connects to the reservoir, allowing you to remove the reservoir from the pack without undoing any hose routing. This feature makes removing and inserting the reservoir into the pack much easier. The Osprey Syncro 12 features a mid-point quick-release button that allows you to disconnect the hose before you remove the reservoir from the pack. Many models in our lineup also have a separate bladder pocket in the pack and wide-mouth reservoir openings that make removing, refilling, and replacing a breeze.
One of the most important aspects of this metric is the size of the reservoir's opening. Some reservoirs have quick release hoses and wide mouth openings that span the entire width of the bag, while others have screw-top lids built into the side.
Using the Quick Connect on the Rush 8L Hydration Vest's HydraPak reservoir.
Reservoirs made by HydraPak (found on Evoc and USWE packs), Osprey's Hydraulics reservoir, and Deuter's Streamer reservoir all have wide mouth openings. These openings run the width of the reservoir, are easy to place under a faucet to fill, and are large enough to put ice cubes into. This design is also the best for filling up in trickling streams (be sure to add a chemical treatment in the reservoir or an in-line filter to the hose).
A small, integrated handle provides a place to hold the reservoir as it's being filled.
Credit: Tara Reddinger-Adams
CamelBak and Gregory reservoirs feature screw-top openings and integrated handles, making holding them under the faucet much easier. Our testers enjoy these integrated handles' support, especially as the water begins to weigh down the reservoir as it fills.
Large handles, quick disconnect hoses, and large openings all make a bladder easier to fill.
Credit: Tara Reddinger-Adams
How important this metric is to you may depend on where you usually fill your hydration reservoir. Do you always fill from a kitchen sink? Do you ever travel and fill your reservoir from a shallow hotel sink? How about filling on the go from natural sources like lakes and streams? As water sources become less convenient, the convenience of the opening becomes more critical. The size of the reservoir opening can make a significant difference in the time and effort it takes to fill. A wider opening generally makes filling up easier.
Our testers found that putting a full side load bladder back into its pocket was easiest when the main body of the pack was not full.
Credit: Tara Reddinger-Adams
The reservoir compartment design also impacts how easy it is to fill. If the pack has a small pocket for the bladder, placing a full reservoir into it can be an exercise in frustration, with a lot of shaking of the pack to get the reservoir into its pocket. Luckily, many packs have pockets that zip open wide, allowing a full reservoir to slide in easily. The USWE Rush 8L Hydration Vest and CamelBak Classic Light each have a zipper near the top of the pack to access the reservoir pocket. Other top-loading designs include the Gregory Endo 15, Evoc Ride 12L, and Osprey Syncro 12 which are easy to put a full reservoir into. Most of these contenders have dedicated hydration bladder sleeves, making the reservoir easily accessible, even when the bag is stuffed with gear.
Packs such as the CamelBak M.U.L.E. Pro 14 and the Deuter Compact EXP 14 use a side-load system, where the side of the pack unzips to access the bladder. We found it harder to insert full bladders into side-load designs when the pack was full. The minimalist USWE Outlander Pro 2L is made to carry water and not much more and has a small reservoir pocket. In our testing, we had to shake the pack to get a full 2 liter reservoir into the pack. The easier it is to refill your pack, especially during a hike or ride, the easier it is to ensure you drink enough water to stay hydrated. With most of today's pack designs, there is no need to dump your pack's contents in frustration to refill your tank.
A large zippered opening helps to make accessing the water reservoir a breeze.
Credit: Tara Reddinger-Adams
Comfort
A pack's level of comfort includes several factors. One of the first things we looked at was the intended use of all our test packs. Is the pack designed to carry water and not much else like the CamelBak Classic Light or USWE Outlander Pro 2L? Is it intended to carry and organize your mountain biking gear like the Evoc Ride 12 or Gregory Endo 15? Is it designed to fit like a vest, like USWE Rush 8L Hydration Vest is? Or, is it designed for all-day adventures like the Osprey Skarab 18 or the Deuter Compact EXP 14? In some packs, such as the CamelBak M.U.L.E. Pro 14, you can add back protection for mountain biking, making them even more activity-specific. Considering how you will use your hydration pack will help narrow your choices and is an important step in your hunt.
Loading down an ultralight pack with too much weight can diminish its comfort. Conversely, a large pack may be overkill if you carry minimal items and only partially fill your hydration bladder. Having too large of a pack isn't necessarily uncomfortable, but its contents may shift around more during use than in a smaller pack. These factors can decrease your comfort, and the size and weight of items you carry should be considered when looking for a new pack.
No Dancing Monkey harness is designed to prevent loads from bouncing around during activity.
Credit: Byron Adams
We kept our comparison loads similarly weighted during testing. We typically carried a medium-sized first aid kit, a wind jacket, two liters of water, some snacks, a lip balm, and a cell phone for hiking. On certain occasions, we also lashed our trekking poles to the pack. We carried those same essentials on mountain bike rides, plus multitools and a small bike repair kit. Beyond these staple activities, we also used the packs as a multipurpose pack and while walking the dog. The smaller models we tested did not have the capacity for all these items, but the 8 liter and larger models we tested proved versatile and could be compared while carrying a more substantial load.
Next, we looked at each hydration pack's overall construction and tested how it supports and carries a load. Each model in our lineup has one of three basic foundations: No frame, like the USWE models and the CamelBak Classic Light, a stiffened foam frame sheet, like our value-oriented Gregory Nano 18 H2O, and a light wireframe like the high-end Osprey Syncro 12.
Each of these backs has a different back panel design intended to increase airflow by keeping a majority of the pack off your back.
Credit: Tara Reddinger-Adams
Packs without a frame are more comfortable with lower weights and tend to slump and cling to your back as you add weight. Packs with stiffened foam or wireframes distribute weight better and are more comfortable. We were pleasantly surprised at the support we felt when we loaded the Osprey Skarab 18 up with a full day's backcountry gear and started hiking. It doesn't provide the degree of support a specialized ski pack does, but it isn't explicitly designed for that. The Deuter Compact EXP 14 is made for larger loads. It expands up to 19 liters and handles the additional weight quite comfortably.
We also tested these packs for breathability as this affects your comfort quite a bit (think a sweat-saturated back on a chilly and windy day). The wire-framed Osprey Syncro 12 and Deuter Compact EXP 14 with their Airstripes and AirMesh lining provide the best ventilation designs. They offer high levels of breathability by keeping the pack's main body away from your back, allowing for greater airflow. The Gregory Endo 15 also provides decent ventilation with comfortable back panels separated from the backpack's body. However, packs that lack a wire frame, such as the CamelBak Classic Light, USWE Outlander Pro 2L, and USWE Rush 8L Hydration Vest all sit directly against the back, preventing airflow and leaving us sweaty.
Some packs sit directly against your back and rely on mesh fabrics to wick sweat away. In our testing we found these packs to be warmer than those with a frame or channels that allow airflow between the pack and back.
Credit: Tara Reddinger-Adams
Shoulder strap construction is another important consideration when it comes to comfort. Much of the pack's weight rides on your shoulders, especially for models with no hip belt or a skinny webbing belt. Shoulder straps with a more anatomic cut are more comfortable. During our testing, we found the shoulder strap design of some packs to be uncomfortable and too tight for people with larger torsos. Ultimately, the higher-priced packs in our lineup tend to have more adjustability and ergonomic designs that are more comfortable for a wider range of body shapes.
If you're on the fence about hip belts, check out models that offer it as a removable feature.
Most packs in our review use a traditional shoulder strap, which you can tighten by pulling on the lower part of the straps, generally allowing various body types to achieve a comfortable fit.
USWE separate themselves utilizing their patented No Dancing Monkey™ harness, whose buckle is in the middle of the chest. The USWE Rush 8L has no shoulder strap adjustment and instead adjusts with elastic shock cord straps on the sides of the vest. For this pack, you must measure your chest and use their fit guide to ensure a proper fit. In our testing, we found the fit of this design to be highly dependent on the shape and size of one's torso, and some of our female testers experienced a less-than-desirable fit. The harness on the USWE Outlander Pro 2L adjusts with dual Velcro loops at the bottom of the strap, but there is no adjustment for the strap that fits over the shoulder. Our female testers could not comfortably wear the USWE Outlander Pro 2L. No matter the adjustments, the buckle sat towards the top of our sternum, and the straps smashed our female testers' chests, making it very uncomfortable to wear. However, male testers found the pack generally comfortable.
Our female testers had difficulty getting the buckle to sit below the sternum.
Our female testers found some packs uncomfortable because of their strap and buckle placement.
Our female testers had trouble getting these packs to fit properly and comfortably.
Some hydration pack users prefer a more substantial hip belt like the Thule Vital 6 and Deuter Compact EXP 14, while others have no hip belt, like the USWE models, which rely on their No Dancing Monkey™ harness. Others use a slightly wider, larger webbing design, like the Evoc Ride 12, while still others have a thin hip belt, like the Osprey Syncro 12 and Gregory Nano 18 H2O. What type of waist security you prefer is very subjective, and only you can decide which style you like. Generally speaking, the more substantial the hip belt, the more comfortably the bag will carry heavier loads.
For light loads a pack with a smaller waist belt can work well.
Credit: Byron Adams
Storage
A pack's comfort is a cocktail of individual ingredients, while storage space is more straightforward. Are you only carrying water? Do you regularly carry extras in your pack, like snacks, first aid, and an extra layer? How about carrying tools, emergency gear, and other items for remote or all-day adventures? Depending on your typical day out and what you bring, it's relatively easy to figure out how much space you need.
Once you've decided on the best size, you can begin narrowing down how you want your storage space organized. Do you prefer one large opening to stuff all of your contents into? If so, the Gregory Nano 18 H2O may be the ticket with its basic sack-like style. Are you someone who loves to have everything in its compartment or pocket? Some packs even have loops to hold your bike pump in place, pad and helmet carry straps, integrated rain covers, and lots of interior pockets. If this is your style, our midsize bike packs, such as the CamelBak M.U.L.E. Pro 14, the Gregory Endo 15, and the Osprey Syncro 12 can be great choices.
The lightweight USWE Rush 8L Hydration Vest pack has easy-to-access storage pockets on the shoulder straps that come in handy. In addition, there is storage in the pack's body.
Credit: Byron Adams
We were especially impressed with the storage features on the Gregory Endo 15 and Deuter Compact EXP 14. The Endo has 15 liters of overall volume, lots of storage compartments, zippered pockets, padded sleeves, and hip belt pockets. The EXP14 also has loads of pockets, and its main storage pocket can expand by a full 5 liters, making it a great choice for all-day outings. We also like the easy-to-use storage compartments in the Evoc Ride 12, whose rectangular shape is easy to stuff with first aid and extra layers.
Sometimes, you get creative with your pack's storage. Here a helmet holder is used to help secure a pair of hiking boots to the pack.
Credit: Tara Reddinger-Adams
Weight
At GearLab, we measure an item's weight since sometimes claimed weights aren't always accurate. Our lineup of hydration packs is no exception. We weighed each pack on a kitchen or handheld luggage scale with its included hydration system to get our listed weights.
The packs in our review range from lightweight minimalist models to those for all-day excursions, and their weight reflects those differences. Some of the lightest packs in our test include the CamelBak Classic Light at 14.5 ounces, the USWE Outlander Pro at 17.6 ounces, and the USWE Rush 8L Hydration Vest at 19.2 ounces. Of these sub-20-ounce packs, the Rush 8L stands out due to its 8 liter carrying capacity, which is 6 liters more than the Classic Light and Outlander Pro.
This pack's storage is impressive, considering it weighs just 19.2 ounces (1.2 pounds).
Credit: Tara Reddinger-Adams
The fully-featured Deuter Compact EXP 14 is at the opposite end of the spectrum, which tips the scales at 41.6 ounces. This pack is expandable to 19 liters and has enough storage for all-day adventures. The Evoc Ride 12L came in at a respectable 24 ounces, and the Osprey Skarab 18 at 25.5 ounces.
The Classic Light weighs a scant 14.5 ounces even with its hydration bladder and hose.
Credit: Tara Reddinger-Adams
With its simple, lightweight design, the CamelBak Classic Light scores well in this metric. If you carry just the bare necessities and don't need more than 2 liters of water, this pack is an excellent choice and is comfortable whether you're a cyclist, hiker, or runner. It has shock cord straps and a storage pocket on the pack's main body for added storage and versatility. It's also an excellent choice for kids, keeping the pup hydrated, or occasional hydration pack users.
The EXP 14 is the heaviest pack in our test tipping the scales at 41.6 ounces.
Credit: Tara Reddinger-Adams
How much emphasis this metric has on your hydration pack decision-making is up to you. Some riders and runners want things as light as possible, whereas others don't mind an extra few ounces or even a pound if it means their pack is more organized, comfortable, and has more bells and whistles.
It's up to you to determine how much value the extra weight of additional pockets and features brings to your intended adventures.
Credit: Nick Bruckbauer
Ease of Cleaning
Cleaning your pack's reservoir is generally the last thing you want to do when you get home, and many of us don't clean our reservoir as often as we should. The reservoir's design can make cleaning easier. Wide mouth openings allow you to easily insert a brush or hand into the reservoir to scrub it out and help prevent mold and bacteria from overtaking your reservoir.
Features like quick-connect hoses also make it easier to remove and clean the reservoir, hose, and bite valve (where mold seems to thrive). The reservoirs with the widest opening mouths were those made by Deuter and HydraPak, whose reservoirs are found in the Evoc Ride 12 and USWE packs, and those found in the Osprey Skarab 18 and Syncro 12. Their wide openings make it easy to insert your hand or bush, scrub, and dry. Once you do it, you realize that keeping the bladder clean is pretty darn easy. Cleaning the hose requires a specialized thin brush, but removing these bite valves and scrubbing them or soaking them to remove bacteria is easy. HydraPak reservoirs found on Evoc, Osprey,and USWE packs can be turned inside out to clean. For those that are dishwasher safe, you can toss them inside out in the top rack and let the machine do the work.
Wide mouth openings make cleaning the reservoir much easier.
Credit: Tara Reddinger-Adams
The narrower the opening, the more of a task cleaning becomes. The packs equipped with CamelBak Crux reservoir fill easily but are harder to thoroughly clean and dry than the models mentioned above. That's not to say they were that difficult to clean; they just require a brush or small hand and a bit more effort than the other wider opening models. The reservoir found in the Teton Sports Oasis and the 3D-Hydro system reservoirs on the Gregory Nano 18 H20 and the Endo 15 require a little more effort, with smaller circular openings requiring the right size brush to clean.
The Quick Dry Hanger on the Gregory 3D-Hydro systems is a nice touch to help empty and dry out the bladder.
Credit: Nick Bruckbauer
After cleaning, allow the reservoir to dry completely to avoid growing bacteria or mold inside. If possible, towel dry the inside of the bladder and place it on a windowsill, propped open with a kitchen utensil (think a large whisk or wooden spoon) to speed up the drying process. You can also keep the empty bladder in your freezer to limit bacteria growth during storage.
With so many great packs on the market, you'll want to find the one that best meets most of your needs.
Credit: Tara Reddinger-Adams
Conclusion
The process may seem overwhelming with so many hydration packs on the market and specialized options available. Our goal is to provide the best research, detailed testing, and helpful tips so that you can find the best hydration pack for your needs.
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Tara Reddinger-Adams, Nick Bruckbauer, & Jason Cronk
