REI Magma 10 Review

REI Magma 10 Overview

The REI Magma 10 is a new bag on the block, bringing a relatively minimalistic design to the REI sleeping bag lineup. The simplified baffle pattern and draft collar are made with high quality nylon fabric and come stuffed with premium goose down (none of that subpar moose down, thank you very much).

We recently reviewed the REI Igneo 17 sleeping bag and awarded it our Classic Pick for the Wilderness Backpacker. The Magma 10 and 17 raise the bar as REI’s premium line of bags, offering more warmth, less weight, tighter compression, and an updated design with thinner materials.

For these reasons, and its outstanding versatility and comfort for a mummy bag, we’re awarding the REI Magma our Classic Pick for the Ultralight Backpacker.

Continue reading below to live vicariously through our experiences with the men’s REI Magma 10 sleeping bag, and browse our comprehensive Sleeping Bag and Backpacking Quilt Guide to figure out which style is right for you.

REI Magma 10 Star Rating
  • Comfort
  • Warmth
  • Durability
  • Fit


The REI Magma 10 sleeping bag will lift your Zs to lofty new heights. The simple design is forged from premium components, creating a sleeping bag that is lightweight and warm enough for almost any adventure you can dream of.

Update: We tested the Magma 10 in 2018. In 2019 REI discontinued the Magma 10, and instead offers the Magma 15. The main difference is temperature rating — the 15 has an ISO Lower Limit rating of 16 degrees F, rather than 10 degrees. Small tweaks were done, but the down fill, fabric materials, and general fit is the same. The new bag is $369,  a $20 increase, and is not as warm. This change makes it less of affordable, and we feel so-so about the change. We have updated our purchase options to the Magma 15 for men and women.

REI Magma 10 Specifications

Feature Type Feature Specs What This Means
Weight 1 lb 14 oz. (850 g) Well under two pounds for a fully featured sleeping bag. Quite light.
Type Mummy Bag This mummy shape is quite fitted, but has room in the shoulders. For more info on the difference between quilts and sleeping bags read our guide.
Size Regular, 72″ (182 cm), Long, 78″ (198 cm) Standard sizes for men.
EN Testing EN Lower: 10 Degrees, EN Comfort: 22 Degrees The Magma 10 will keep you warm at 10 degrees, and toasty at 22. A very warm bag. Read more about how temperature ratings are determined in our guide.
Insulation Type 850-Fill Goose Down High quality goose down. Read more about sleeping bag insulation in our Guide.
Fill Weight 17.6 oz (500 g) More than half the weight of the Magma 10 is just goose down, which tells you just how warm it is. Very.
Shell Fabric Pertex 15D Ripstop Nylon, Bluesign Approved A thin but durable shell from Pertex, the leader in shell fabrics. Read more on sleeping bag and quilt shell fabric material in our Guide.
Water Resistant? Yes The down is “water-resistant”, though REI doesn’t claim how or by what process.
Baffle Pattern Horizontal Standard horizontal baffles on the Magma 10. Read more on sleeping bag and quilt baffle patterns in our Guide.
Zipper Length, Type, Placement Full Length Left, Hybrid Path A solid zip with a functional anti-snap pull. The zipper comes over the shoulder for better comfort, warmth, and getting out of the bag.
Draft Tube? Yes A full-length draft tube along the zipper keeps out the cold.
Neck Baffle? Yes An insulated yoke sits behind the neck and shoulders to keep you totally toasty.
Pocket? No This is an ultralight, 100% function-based bag. No pockets.
Manufacturer Warranty Limited Lifetime REI claims this has a limited lifetime warranty, but it can be hard to call that in many years later. You can return the bag no questions asked within a year of purchase.
Retail Price $350 A high price for our Classic Pick, but the quality is top notch and competes with much pricier bags for the warmth and weight.

Gear Review of the REI Magma 10

Origins: Easing You In

Springtime is a period of transition. As the days grow warmer in Oregon’s North Umpqua Forest the mountain streams swell with snowmelt as riverside wildflowers are reborn by the lengthening days of bright sunlight. Though sunny spring days can get quite warm, the nights, especially in the mountains, still retain some of winter’s frosty bite.

That’s why I brought the REI Magma 10 sleeping bag on my backpacking trip along the 79 mile North Umpqua Trail in Oregon’s Cascade Mountain Range, where evening temperatures plummeted to near or below freezing during each night of my hike. The Magma’s 10 degree limit was enough to keep me quite warm and its minuscule weight meant that it wouldn’t be a burden to the high mileage I was aiming for as I cruised down the trail.


The REI Magma 10 is really light. So light you can hold it all by yourself! Really though.

Though the Magma’s compressibility and insubstantial weight make it ideal for backpacking, I found the bag to be so cozy on my North Umpqua hike that I opted to take it out again for some car camping in the desert east of the Umpqua National Forest. From wet forest to dry desert, and from cold to colder, the Magma’s down insulation kept me snug like a bug in a rug — a very fluffy rug.

Revelation: The Moment I Knew

That first night on the North Umpqua Trail was all the experience I needed to know that the REI Magma sleeping bag is worth its weight in goose down, which is better than gold as far as I’m concerned.

I found the first day of this hike to be the most exhausting. Pumped full of enthusiasm for the trail ahead, I hiked hard right out of the gate with all of the pent up outdoor energy I had been stashing away. Winter was over and I was excited to walk! But after driving up 5000 feet in elevation to my starting point I should have known to give my body some time to adjust.


Clouds and deep green on the North Umpqua Trail.

Who am I kidding, though? I like to hike hard. The high elevation paired with a full day of cold rain left me wiped by the time I hit 22 miles for the day. As soon as I setup camp I launched myself into the REI Magma sleeping bag like a fox into a rabbit hole.


Well fitted, crazy warm, and delightful after any hike. This is a different trip than North Umpqua Trail hiike, but the bag was equally cozy.

I’ve said it before and I’ll say it again: the best part of backpacking is slipping into your sleeping bag at the end of the day. The REI Magma is pumped full of 850-fill down which makes it fricken fluffy. Seeing the lofty bag grow in size after being pulled out of its stuff sack was like watching one of those science class experiments where buckets of foam pour out of a tiny test tube.

The REI Magma 10 liner was a treat against my skin. I was covered in goosebumps as I got in the bag, and it was the goose down which warmed them away — it was like a blanket made of snuggles and irony. I slept as hard that night as I had hiked that day.


That fluff.

My waking thought the next morning (Ahhh…fluffy bag…mmm) brought a smile to my face.

Digging Deeper

That oh-so-fluffy down is harvested following the Responsible Down Standard, meaning that the puff in your Magma comes from geese that were not subjected to any unnecessary harm. The 850-fill power is almost as high-quality as down gets, and the amount used in the REI Magma (17.6 ounces of pure down) insulates to a lower survival limit of 10 degrees, which is quite warm. The EN Comfort rating keeps you plenty comfortable at 22 degrees, and for most men this means temps between 15-30 degrees will be toasty. Such great insulation can sometimes mean a heavy weight, but a regular-sized Magma balances the scale at a quite light 1 pound 14 ounces — which won’t weigh you down (pun intended).


The EN Temperature rating for the REI Magma 10. It’s warm.

The 15D ripstop nylon shell is pleasant to touch and fairly durable. REI “double-downed” (enough with the lofty puns, I know) on the environmental impact of the Magma by making sure the fabric was bluesign approved, ensuring that you receive a product that was fully created with environmental protection and consumer safety in mind.

The Magma is a fitted mummy bag with a covered zipper that wraps over your shoulders. The adjustable hood comes paired with an insulated yoke (aka draft collar), which can be used to protect your neck and face in extreme weather conditions.

The woman’s version is called the Magma 17. It’s a bit heavier at 2 pounds 4 ounces, but it has a lower survival limit of 3 degrees and is comfortable down to 17 degrees, making it a great bag for women who sleep cold.

Comfort 5 Stars

The Magma has a roomy fit despite being a mummy, and it gives you enough space to roll around in its big, fluffy mass. I made use of the hood adjustments and collar yoke to find the right balance of insulation I needed as the temperature dropped and winds shifted through the nights.


A mummy bag through and through, the REI Magma 10 hugs your shape. It’s wide in all the right places though, and traps in the heat.

Warmth 5 Stars

This is a warm bag, for sure. I tested it to as low as the mid 20s and never felt uncomfortable while only wearing a shirt and briefs. If needed I could have covered my entire face with the collar yoke and reigned in the hood to completely seal myself in, but it never got to that point. I feel that I would have been fine without additional clothing layers even if the temperature dropped into the teens, and I’d have to take off the last of my layers if it were to get any warmer!

Durability 4 Stars

The fabric, baffle stitching, and covered zipper all feel reliable. Though I haven’t tested this bag extensively, I’d expect all of those elements to last a long time. The hood adjustment, however, is questionable. The elastic cord you pull is the weakest point of the entire bag, and, in fact, is already showing some signs of fraying after minimal use.


The YKK zipper pull is unique to REI, and works well to stop snags.

Fit 5 Stars

I like a little wiggle room, and this mummy bag has plenty. I’m 5’10 at 180 pounds and the men’s regular fit me just fine in all areas: head, shoulders, knees and toes — knees and toes. The Magma 17 is not only warmer but also has a female specific fit.


Overall this is an excellent bag from REI, one that uses premium materials at a fraction of the price these bags usually go far.

That said, I’m disappointed to see fraying on the hood adjustment after only a couple of uses. Everything else about this bag is wonderful, but that one spot leaves me feeling concerned that I’d have to get it repaired within a year of use.


A closeup of the hood adjustment. The cord is fraying a bit after initial use, which doesn’t bode well.

Final Word

The REI Magma 10 sleeping bag will lift your Zs to lofty new heights. The simple design is forged from premium components, creating a sleeping bag that is lightweight and warm enough for almost any adventure you can dream of.

Where to Buy REI Magma 10

We tested the REI Magma 10 sleeping bag, which is specifically made for men. The REI Magma 17 is the women’s specific bag, and while the features are generally the same, the fit is meant for women (narrower shoulders and wider hips) and it weighs four ounces more than the men’s. The temperature range is different because women typically sleep colder than men, so this is a very warm bag by all standards.

In 2019 REI discontinued the Magma 10, and instead offers the Magma 15. We have updated our purchase options to the Magma 15 for men and women.

Arthur McMahon

Arthur loves to walk. It's as simple as that. He believes walking is the best way to experience the world. Thru-hiking the Pacific Crest Trail was his first backpacking foray, and he hasn't stopped since. Follow his adventures and stories on Instagram.

Review Policy: We do not accept payments or gifts from brands and vendors, and strive to provide unbiased, independent advice. Brands typically provide review samples which we return, and in some cases we purchase the item so we can keep using it long after the review. Affiliate Policy: We support the hours that go into our reviews and testing through affiliate commissions on purchases made through links in this article. These don't effect the outcome of our reviews or selection of gear, as per our Review Policy.

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