How to Choose a Sleeping Bag: Six Things to Consider

Most outfitters and outdoor stores leave the average person reeling from all the information they are force fed in order to make an educated purchase. If you aren’t lucky enough to come across a seasoned employee who is willing to listen to your needs and slim down your options, it is all too easy to walk out with the incorrect product. If you are looking to arm yourself with the gift of warmth while in the woods, here is a guide to buying the right sleeping bag for your needs.

The Six Things to Consider

1. EN Rating


This is a very small depiction of the EN testing process. A copper dummy in your typical base layer clothing is thrown into the sleeping bag, on a sleeping pad and wired up with a couple of scientific nodes attached to him. Based off of the data gathered, an EN is found.


The EN, or European Norm, rating system denotes the degree at which a bag is rated down to. When most people look at sleeping bags, this is where their attention falls first. If you only want a bag for occasional summer camping trips, you can easily get away with a higher rated bag at 45° or 55°. If you are looking to begin a thru hike in early March, you are better off around the 15° mark. (Keep in mind that you’re lucky if it never falls below 15° on the AT in early spring.)  Most sleeping bag companies use EN ratings to derive the temperatures for their bags. However, there are other numbers that can be used to determine if a bag is the correct temperature for you. Many bags also give you the Comfort rating (mostly pertains to women), the Limit rating (mostly pertains to men), as well as the Extreme rating (basically, how cold it can be with out you dying). The difference in the Comfort and the Limit rating have to do with body make up. In general, women sleep colder than men, thus makers of bags include the comfortable sleeping temperatures of a typical woman and man for each particular bag. Women’s bags have more down than most men’s bags and it is distributed in certain places for maximum comfort. However, in a pinch a men’s bag can be used for a woman, but as a general rule knock off 10° of warmth for a more accurate comfort rating. (ex: a men’s 25° bag would become a 35° bag for a woman)

 2. Down or Synthetic


Down is an age-old material of warmth but synthetic fibers come with their own benefits. Besides being the only option for those who are allergic to down, the most notable perk of a synthetic bag is that it will still retain its heating capabilities when wet. If for some reason your sleeping bag follows you into a river, you’d be much better off if it were synthetic. When a bag is soaked through, down becomes next to worthless as a far as retaining heat. Of course, no one plans on a soaking wet sleeping bag. For many, the benefits of down far out way the risks of it. Down is much lighter weight and much more compact than synthetic fibers are. This goes a long way in winning the heart of someone who knows they have to carry it for six months.

3. Down Fill


The fill count of a down bag refers to the quality of the down feathers inside. A 550-fill bag will have smaller, more compact down particles with less loft than an 800-fill bag. The better the loft, the more air there is allowed into the down, thus a warmer bag. At least, once you sit in there and shove out your body heat for a while.  The 800-fill bag will also be much smaller because it takes less down of that quality to reach the assigned EN. Finding out the fill of your bag will also inform you of whether duck or goose down was used. (Allergies to the down of specific birds is a real thing!)

500-550 fill = good          550-700 fill – very good          700+ fill = excellent

4. Weight


It’s cute, but it’s not smart to carry it around.

A decent sleeping bag for early spring backpacking can be a pretty weighty (as well as sizable) purchase. To slim down that bundle at the bottom of your pack, keep the first three considerations in mind. Things that weigh your bag down are: low ratings (probably don’t need a 0° bag), your material choice (switch to down to lighten up a bit), and the fill count of the bag (if you already have a down bag picked out, look for one with a higher fill count to get a smaller and lighter bag).

5. Compression


Most sleeping bags will supply you with the number of liters the bag fills when simply stuffed in a sack, as well as when it is compressed down to its smallest size. Generally speaking, a compression size of about 8 liters is the max you would want for backpacking. Anything more than this begins to take up more room than you would want in a backpack. Anything less just gives you more room for Oreos and Sour Gummy Worms! Always do yourself the favor of compressing your sleeping bag. No matter how big your backpack, it is always a space saver. If you are worried about a down bag getting wet, buy a dry compression sack for it. Then line your pack with a trash compactor bag and even if you do fall in a river with it, that sucker is well protected!

6. Price


As all hikers know, there is always a give and take with the price of gear. Obviously, your most effective, lightest, smallest sleeping bag will cost you your first-born child. You could pay $400+ on a 10° 900-fill down bag that weighs just barely over a pound. Or you could pay $100 on a 33° synthetic bag that weighs over three pounds. By finding out your hiking style (ultra light, light weight, or kitchen sink carrier) you can find out how much you need to funnel into this piece of gear to get what is going to work for you. At very least, shoot for a happy medium between pinching pennies and a top of the line sleeping bag.


Like to toss and turn a lot in your sleep or have a fear of a mummy bags?

Check out Big Agnes Sleeping Bags. They made a few wider options for those who need to kick round a bit. Particularly, the Hog Park for men and the Lulu for women.


Don’t need THAT much space but still wish your feet weren’t bound up at night?

Check out Nemo, who makes a few “spoon” bags that offer a good bit more room in the toe box.  The Nemo Nocturne 15 and Nemo Nocturne 30 were selected as the editor’s choice by Backpacker Magazine.


Have a sleeping bag already and wish you could make it just a tad bit warmer?

Sea to Summit makes several sleeping bag liners that when used in conjunction bring down the EN of a sleeping bag to make it warmer.


Personal Choices:

For my thru hike in 2013, I chose an REI Halo 10° bag. When I was walking through a week of snow in the Smokies, I loved it! When I was trying to force it into a stuff sack and get it in to my pack, not so much (that is a learned skill). It was a big guy but I never had a cold night on the trail, at least once I got in it. It is 2lb. 12 oz., 750-fill and compressed down pretty well considering the alarming amount of loft of this bag. We’re talking serious fluff here! As for the price, it was originally $299 but REI no longer makes them and I actually caught this bag on clearance as they were going out the door (lucky me!).


But with such a cozy and warm bag, I had to have a second for when summer was in full swing. This second bag was a REI Halo 40° bag. I obviously don’t like to be cold so even when it was 90°+ all day and barely in the 60’s at night, I was still rocking the 40° bag. Like the last, it was 750-fill but this guy sits at around an pound and a half for its weight and compresses amazingly. Just as the last, it is no longer made but I scooped it up for about $70 at a REI Garage Sale (formerly known as Scratch and Dent Sales).



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Comments 1

  • robert : Oct 14th

    Great article! And those REI garage sales at great. I just got a nemo nucturne 30 for $80!


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