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Western Mountaineering Kodiak MF Review

For temps down to zero degrees, you can't beat this lightweight but very warm bag
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Western Mountaineering Kodiak MF Review
Credit: Backcountry
Price:  $875 List
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Manufacturer:   Western Mountaineering
By Matt Bento ⋅ Review Editor  ⋅  Feb 20, 2025
76
OVERALL
SCORE


RANKED
#1 of 13
  • Warmth - 20% 8.0
  • Weight - 20% 7.0
  • Comfort - 20% 8.5
  • Packed Size - 15% 7.5
  • Weather Resistance - 15% 7.0
  • Features - 10% 7.0

Our Verdict

The Western Mountaineering Kodiak MF is our test team's absolute favorite sleeping bag. A perfect balance of warmth, weight, and comfort, the Kodiak has all the same great features as other western bags, but adds several inches of girth in the shoulders and even more down insulation. We look at the specs on this bag and find it hard to fathom how a sleeping bag can be so light and compressible and still so warm. The Kodiak compresses as small as bags that aren't as warm, yet still somehow lofts back to an incredible seven fluffy inches whenever you unpack it. Packability, warmth, roominess, and the quality most folks expect from the manufacturer put this model ahead of the pack. To see how the rest of our lineup measures up, see our full review of winter sleeping bags.
REASONS TO BUY
Warm
Awesome comfort
Great warmth to weight ratio
REASONS TO AVOID
Expensive

Compare to Similar Products

 
Awards Editors' Choice Award
Best Overall Winter Sleeping Bag
Top Pick Award
Best Simple Design with Weather-Resistance
Top Pick Award
Best for Fast and Light Winter Camping
Top Pick Award
Most Comfortable Design
Best Buy Award
Best Bang for Your Buck
Price $875.00 at Amazon
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Overall Score Sort Icon
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Bottom Line This bag is the cream of the crop when it comes to loft and comfortThis lightweight sleeping bag comfortably cradles you with warm, lofty downExcellent for moving in the mountains in cold weather, this model is lightweight, packs small, and stays true to its temperature ratingLoaded with features, this bag is great for those looking for a little luxury in the backcountryThis budget bag offers protection from the elements via a large draft tube and plush draft collar
Rating Categories Western Mountaineer... The North Face Infe... Mountain Hardwear P... NEMO Sonic 0 Mountain Hardwear B...
Warmth (20%)
8.0
8.0
8.1
6.0
7.0
Weight (20%)
7.0
8.0
8.0
6.0
6.0
Comfort (20%)
8.5
7.0
6.0
9.0
6.0
Packed Size (15%)
7.5
6.0
8.0
6.0
5.0
Weather Resistance (15%)
7.0
9.0
6.0
7.0
7.0
Features (10%)
7.0
6.0
8.0
9.0
6.0
Specifications Western Mountaineer... The North Face Infe... Mountain Hardwear P... NEMO Sonic 0 Mountain Hardwear B...
Measured Weight (size Regular) 2.85 lbs 2.68 lbs 2.68 lbs 2.95 lbs 3.13 lbs
Fill Weight 30.0 oz 29 oz 29.6 oz 24.0 oz 35.0 oz
Type of Down Fill Goose Down Down RDS Certified Goose Down RDS Cert/Fluorine Free Down RDS Certified Down
Fill Power 850 800 850 800 650
Material Weight (excludes down filling) 15.7 oz 13.9 oz 13.3 oz 23.3 oz 15.1 oz
Temperature Rating 0°F 0°F 0°F 0°F 0°F
Pocket No No Yes Yes Yes
Shoulder Girth 66" 64" 58" 61" 62"
Hip Girth 57" 60" 52" 58" 53"
Foot Girth 41" 44" Not listed 53" Not listed
Shell Material MicroLite XP 15D recycled nylon, 30D nylon taffeta 10D Nylon Ghost ripstop, DWR finish 20D nylon ripstop, DWR treatment 20-Denier ripstop nylon
Continuous Baffle Yes Not listed No Yes Yes

Our Analysis and Test Results

Performance Comparison


western mountaineering kodiak mf - somewhere in all that lofty goodness is a very warm human. the...
Somewhere in all that lofty goodness is a very warm human. The Kodiak employs 1.9 pounds of 850 fill down, giving it one of the best warmth-to-weight ratios out there.
Credit: Matt Bento

Warmth


What does 30 ounces of 850-fill down look like? When unstuffed, laid out, and fully lofted, it creates 7 inches of insulated space on top of your body, making this bag exceptionally warm. Western Mountaineering doesn't use EN ratings or give any sort of comfort range. Their website just states that the Kodiak is a zero-degree bag. After testing many brands, we feel that Western Mountaineering is conservative with its temperature ratings. Upon learning that the Kodiak had a similar rating as some other 0-degree bags, one of our testers couldn't stop laughing. It's just that much warmer.


The extra room in the Kodiak's interior that makes this bag so comfy does decrease its thermal efficiency, since there is more uninsulated dead space in the bag, especially if you're a smaller person. If you're in cold weather, you're likely to have a puffy down jacket and other insulating clothes with you to fill that extra space. If you're an alpinist or ultralite backpacker, check out a smaller, more efficient bag.

western mountaineering kodiak mf - the draft collar and the hood both have cinch cords to perfectly...
The draft collar and the hood both have cinch cords to perfectly position the hood. You can keep your face warm and breathe easy without letting cold air into the bag.
Credit: Matt Bento

Weight


The Kodiak tipped our scale at 45.65 ounces (or 2.85 pounds). There are other bags of similar weight, but when you look at the fill weight compared to the weight of the materials, the Kodiak really shines. Of the 46 ounces, a whopping 30 ounces is dedicated to down insulation, and a mere 15.65 ounces remains as the weight of the materials. The Microlite XP shell fabric, zippers, and drawcords are functionally durable and exceptionally lightweight, though we'd suggest you look before you lay down and keep this bag away from sharp rocks, thorns, and your dog.


Comfort


Western Mountaineering knocks it out of the park with this one, and thanks to 66 inches of shoulder room and a soft, thick draft collar, the Kodiak earns top marks in our comfort metric. If you're a larger person, the extra room is a must, but smaller folks can really take advantage of the extra space if they're side or stomach sleepers, since there's so much room to move around. You can also use the extra space to keep essentials like water, batteries, and extra clothes warm through the night.


The hood has plenty of loft and stays in place with two cinch cords, creating a nice air hole without letting cold air in around your neck. The two-way zipper allows for venting if you overestimated how cold it might be, and if you unzip the bag all the way, it makes a pretty cozy down blanket for two.

western mountaineering kodiak mf - this bag has loads of room to roll around and isn't a bad place to...
This bag has loads of room to roll around and isn't a bad place to be stuck in if you're tentbound due to bad weather (which isn't the case on the gorgeous day shown here!)
Credit: Matt Bento

Packed Size


With a little work, we were able to fit the Kodiak into the same stuff sack we used for several bags that had higher temp ratings. Despite the extra fabric that makes this bag roomy, it's still competitively packable, leaving plenty of room in your pack for other wintertime essentials. We're still scratching our heads at how the roomiest bag in our review is so compressible.


western mountaineering kodiak mf - one compressed kodiak next to some can we found lying around...
One compressed Kodiak next to some can we found lying around...
Credit: Matt Bento


Weather Resistance


The Kodiak employs the same Microlite XP fabric as other quality WM bags, a material that our testers have found acceptably water-resistant, having used Western Mountaineering bags for many seasons. Light rain, mist, and frost have never soaked through to the down, and the outside of the bag dries out quickly in the sun. Unless you're sleeping in an inch of standing water or camping exposed to a downpour, you'll stay dry in this bag.


The down fill doesn't have a hydrophobic treatment. Keep in mind that if you need a zero-degree bag, rain isn't the kind of precip you're usually worried about. Also, if you're excited about the dimensions of the Kodiak MF, but you're concerned about wet weather, Western Mountaineering offers a version with Gore-Tex Windstopper fabric, though that version is a little heavier and more expensive.

western mountaineering kodiak mf - microlight xp shell fabric does any an excellent job of keeping all...
Microlight XP shell fabric does any an excellent job of keeping all that down dry and lofty, but remember that it is very water resistant, not waterproof.
Credit: Matt Bento

Features


We've sung the praises of Western Mountaineering's snag-free zipper action and mega lofty draft tubes in the past, and we're happy to keep the tune going with the Kodiak. The firm seam tape on either side of the zipper does an excellent job of protecting the draft tube from snagging, even during late-night, disoriented unzipping in the dark. The draft tube is huge, preventing cold air from creeping in through the zipper. As we mentioned before, the cinch cords on the hood opening and the draft collar keep the hood in place, only exposing your nose and mouth for a comfortable, oxygenating sleep.


This bag doesn't have a small, zippered pocket. A pocket is nice for holding onto earplugs, headlamps, or batteries inside your bag. With the Kodiak, you'll need to bring a tiny stuff sack for those items or find another way to keep them organized.

western mountaineering kodiak mf - like the other western mountaineering bags we reviewed, this bag has...
Like the other Western Mountaineering bags we reviewed, this bag has a thick lofty draft collar and snag-free zippers.
Credit: Matt Bento

western mountaineering kodiak mf - with around an inch of firm tape on either side of the two-way...
With around an inch of firm tape on either side of the two-way zipper, it's easy to open and close in the dark without getting it caught on the draft tube.
Credit: Matt Bento

Should You Buy the Western Mountaineering Kodiak MF?


Western Mountaineering has been at it for a long time, and their product lineup doesn't change very often because their designs are so good. With the Kodiak, they created an extremely roomy, warm bag, that is still lightweight for long, human-powered journeys. If you have a larger body frame, this bag is a must. If you're smaller, prepare yourself for the most luxurious nights you've ever spent in the backcountry. We get to test some amazing sleeping bags in this category from great manufacturers, and sometimes comparing them feels like splitting hairs. That being said, the Kodiak is easily our favorite.

western mountaineering kodiak mf - this is our favorite bag for winter camping and ski touring.
This is our favorite bag for winter camping and ski touring.
Credit: Matt Bento

What Other Cold Weather Sleeping Bags Should You Consider?


We understand that not everybody can afford a bag this expensive. If you want something more affordable, check out the Mountain Hardwear Bishop Pass 0. It's not as warm and doesn't pack down as small, but you could buy nearly three of them for the price of the Kodiak. If you want some weight savings, we recommend the Western Mountaineering Versalite 10, which is over half a pound lighter than the Kodiak (and is slightly cheaper, too). However, it's a 10-degree bag and not as warm.

Matt Bento