Choosing the Perfect Sleeping Bag

When you walk into the store or just Google “sleeping bags,” you may be overwhelmed by all the shapes, sizes, temperature ratings, insulation types, and colors.

Well don’t be discouraged because you’re not alone! With a little research and by reading the tips below, you’ll be picking out your new bag like a pro in no time.

What's your Primary Use?

The first thing to ask yourself when choosing a bag is what you’ll primarily be doing with it.


Driving to the site? You can definitely haul more things with you to your campsite, so space might not be an issue. And since you’re not carrying anything on your back, the weight of the item probably doesn’t matter either. This means you could choose a bag that might be heavier and doesn’t compress super small. As long as it’s warm enough for your needs that’s really all that matters.


So you’re carrying all your gear on your back? You’re probably going to want to find a bag that is fairly lightweight and compresses small to save your back and also space inside your pack. Look for a good warmth to weight ratio and you’ll be happy in no time!


Very similar to backpacking tips here, except you’ll most likely be exposed to much harsher conditions. Keep in mind the temperature rating of your bag for this type of adventure. If it’s going to be super cold, you may want to find a bag that’s rated to 0-degrees or colder.


What Type of Insulation is Right For You?

When it comes to insulation you typically have two choices: down or synthetic. Each has their pros and cons and will keep you just as warm as long as their temperature rating is the same. Warmth comes from the loft, or fluffiness, of the insulation and not the type of insulation.


The feathers from down are usually duck, goose, or some combination of both. The number you’ll usually see associated with down is it’s fill-power; somewhere between 400 and 950.

Now, without getting into the science behind those numbers and how they relate to fill-weight and warmth, we’ll just say that the higher the number is, the easier it is to keep bags and jackets very lightweight and very packable. Higher numbers also mean higher prices. So if weight and compressibility are not issues for you, then lower number fill-powers will work perfectly fine for you! Down sleeping bags will also almost always compress smaller and be lighter weight than their synthetic counterparts.

Down does require a little more care though. It does also not work well at keeping you warm if it’s damp or wet. The weight of the moisture keeps the down from being lofty and, therefore, keeps you less warm. It also takes longer to dry than synthetic insulation. Some companies treat their down with water-resistant treatments to help repel moisture, keep it nice and lofty, and makes it dry a little faster. Make sure to keep your down sleeping bag protected to keep you and your bag warmer and safer!

In summary: Down will keep you warmer in a more lightweight and compressible package, but generally costs more and doesn’t work well when wet.


Synthetic bags are filled with just that, synthetic or man-made materials. These fills don’t have a ratings system like down bags, so the temperature you see on the bag itself is all that matters here. Because the synthetic insulation is easier to acquire, most bags are less expensive than down ones. These bags also require more of the insulation to keep you warm, so they’re going to end up being heavier than an equivalent down bag. The extra insulation inside also means that the compressed size of the bag will be slightly bigger than down too. 

These bags are pretty simple to care for. If they happen to get wet you’ll stay warm, but might sleep a little uncomfortable because you’ll be wet.. Just hang them up over a branch or line and they’ll dry pretty fast too. 

In summary: Synthetic bags perform much better in wet conditions and dry faster than down. It doesn’t compress as small as down bags but is usually friendlier on the wallet.


What Shape: Rectangular or Mummy?

 When I first started camping, probably in elementary or middle school, I thought my sleeping bag was the best of the best. I had the typical rectangle sleeping bag with a plaid pattern interior, and packed down to the completely reasonable size of a large wooden barrel of scotch. I also thought that those mummy bags were for professional adventurers only summiting Everest. Well, now I’ve grown up, gained some experience and knowledge, and have completely changed how I view those bags.

There are now bags for pretty much everyone’s preference. Big ones, small ones, fat ones, skinny ones, adult sizes, kid sizes, hybrids of some, and some that change sizes. I’ll stop before I start sounding like a Dr. Seuss story. But there are really just two main categories:


Rectangular bags have their place for sure. They’re roomy, about the size of a twin bed, so you don’t feel like you’re a wrapped up piece of meat. With this extra size comes more material; which means it won’t pack down as small and can be heavier. You can also find them with all types of insulation and many different temperature ratings.

Just keep in mind though that they are not as effective as conserving heat inside the bag as a mummy bag would be. This is due to the fact that rectangular bags don’t close up around your head very well and allows that heat to escape a little easier. So,if you’re not concerned about saving size or weight, then rectangle bags are great, especially when car camping!

Bonus: You can usually unzip these all the way to have them act like a large blanket!


Mummy bags are the other style that you’ll see when shopping. These bags can feel fairly snug, usually wider in the shoulders and much narrower in the feet. The reason for this is to help warm up the sleeping bag faster. The less space your body has to heat up, the faster you get to feeling nice and toasty. This smaller space though means that you’re supposed to roll over with your bag instead of only inside of it. If you’re a side sleeper like me it may take some getting used to.

Some brands are starting to make mummy-style bags that have slightly more room inside (like Nemo’s Spoon-style bags) or bags that unzip to expand their size. These bags are typically much lighter and pack down considerably smaller than rectangular bags, mostly due to the fact the bag itself is made up of less material.

Temperature Ratings

The single most important feature to pay attention to when bag hunting is the temperature rating. The temperature marked on the bag is the minimum that an average person can sleep comfortably. The ratings are easily identifiable because it’s typically a part of the name of the bag. Salsa 15 means a 15-degree bag, Lost Dog 30 means it’s a 30-degree bag, etc…

When looking at that temperature rating, you really need to only choose a bag that’s going to be rated slightly colder than the coldest nighttime temperature for your trip. So if you hate camping in the winter, then you probably don’t need a 0-degree bag. If you get warm in your bag, you can always unzip it to release that excess heat!

Here’s a super simple breakdown of the temperature ratings on sleeping bags: 30-degrees or more is typically a summer bag, 0-30-degrees is a standard 3-Season bag, and 0-degrees or under is usually a winter bag.


You’ll also want to make sure your sleeping bag fits your pad. You wouldn’t want to but a rectangular sleeping bag and have a mummy-shaped pad would you? Again, Big Agnes has some pretty cool tech on the back of their sleeping bags; they have a mesh sleeve that your sleeping pad and slide right into!



Always Pair a Sleeping Bag with a Sleeping Pad

It’s crucial that you sleep on a sleeping pad. When you are sleeping in your bag, the insulation that is next to ground is being compressed and crushed under your weight, which renders that insulation useless. It’s an absolute must that you insulate that portion of your body from the ground, or your body heat will sucked away surprisingly fast no matter how warm it is at night. Big Agnes actually doesn’t even have insulation on the back of some of their bags for this very reason.


You’ll also want to make sure your sleeping bag fits your pad. You wouldn’t want to but a rectangular sleeping bag and have a mummy-shaped pad would you? Again, Big Agnes has some pretty cool tech on the back of their sleeping bags; they have a mesh sleeve that your sleeping pad and slide right into!

That way, you can feel pretty good about not falling off your pad in the middle of the night and wake up freezing. That’s happened to me a few times and it’s not fun.*

We’ll write more and post about How to Choose a Sleeping Pad and update this post accordingly. 

Other Features to Consider

Once you’ve got your choices narrowed down to maybe just a few bags, here are a few other extra features that don’t affect the performance of the bag but might just be a nice addition to have.


You might not realize how nice it is to have a pocket inside or outside the bag at chest level. You can stash your phone, wallet, keys, headlamp, or flashlight there for easy retrieval. I usually use it for my headlamp, it’s nice to not have to fumble around in your tent trying to figure where you put that thing when nature calls in the middle of the night.


Make sure your bag has nice zippers on it. The right one’s will not be prone to catching the sleeping bag material and potentially ripping your bag or making you become trapped in your bag! Big Agnes has a cool zipper design that pretty much makes it impossible to snag on the material.


Vents in bags are a relatively new find, so some older bags might not have them. Basically, if the temperatures get a little warm at night, you just unzip some vents on the bag to release some heat! Nemo has some cool vents on the tops of their bags. If your bag doesn’t have vents, don’t worry! You can always just unzip your bag for a little bit to let out any excess heat. 


Some bags will have an insulated tube that runs the length of the bag’s zipper to keep air/heat from seeping in or out there. Others have an insulated flap that sits around your neck or shoulders to help prevent heat loss from the hood of the bag.

Let's Sum Up What We've Talked About

Here’s a review of what we talked about:


Are you going to be only car camping, backpacking, mountaineering, or some combination? Choose a bag that will cover you for for most of your needs, you can always buy (or rent) a second bag if you have special requirements for another adventure.


Keep in mind what the conditions will be while you’re out and what your needs are. Down bags will keep you warmer in a more lightweight and compressible package, but generally costs more and doesn’t work well when wet. Synthetic bags perform much better in wet conditions and dry faster than down. It doesn’t compress as small as down bags but is usually friendlier on the wallet.


What your bag is shaped like can affect warmth, weight, size, and sometimes price. The shape you prefer really comes down to what you’ll be mostly be using it for.


Most nice, brand name bags will have the same temperature ratings across the board. I wouldn’t trust big-box store brands or off-brands for the temperature they claim.

  • 30 degrees or more is typically a summer bag

  • 0-30 degrees is a standard 3-Season bag

  • 0 degrees or under is usually a winter bag


Just do it. Never sleep straight on the ground.


There are tons of extra features that can be jammed into bags that can help make your decision if you’re stuck between a few options.


So there you have it, a basic breakdown of how to choose the right sleeping bag for you. Can’t pick just one or have multiple different types of adventures planned? There’s no harm in getting two. Don’t be afraid to spend a little money on them either; they’re a worthy investment. Your life may depend on it and a good night’s sleep is worth it’s weight gold while camping. 

Thanks for reading! See you out there!

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