After a long day of exploring, a good night’s sleep is essential. Sleeping bags come in all kinds of shapes, sizes, and insulation types and you can choose from brands like Big Agnes, MEC, Western Mountaineering, Therm-a-Rest, and Sierra Designs. But how do you know which one is right for your adventures?
Here’s what to think about when you’re choosing a sleeping bag:
- Temperature rating: How cold will it be outside?
- Shape: Do you like a snug, packable bag, or prefer a room to sprawl?
- Size and fit: Choose the right length and fit for your body.
- Insulation type: Down vs. synthetic – learn the pros and cons.
- Features: Extra things to look for warmth and coziness.
- Sleeping accessories: Other gear to help you get a good night’s sleep outside.
- Sleeping bag temperature ratings
- Sleeping bag shapes
- What size sleeping bag to get?
- Sleeping bag insulation: down vs. synthetic
- Down sleeping bag insulation
- Sleeping bag features
- Sleeping accessories
Sleeping bag temperature ratings
A sleeping bag’s temperature ratings tell you the lowest temperature that the bag is intended to keep the average person warm. These ratings assume you’re using a sleeping pad for insulation and are wearing long underwear.
The temperature rating gives you a general idea about performance and is useful for comparing bags. But lots of other factors influence how warm you sleep: hydration, how much you’ve eaten, fatigue, humidity, wind, and dampness. Many brands, including MEC, use the industry-wide EN standard to measure and report the thermal capacity of their sleeping bags.
Sleeping bag temperature ratings are often categorized by season:
|Summer||0°C and up|
|3-season||-15°C to -1°C|
|Winter||-15°C and below|
For the most comfortable sleep, choose a sleeping bag with a temperature rating a few degrees colder than the lowest temperature you plan to camp in. Don’t forget that if you’re camping at higher elevations, it will be colder. If you get warm, you can always unzip your sleeping bag for ventilation.
Sleeping bag shapes
Sleeping bags come in a few different shapes: rectangular, barrel, and mummy (plus quilt options). Some let you sprawl out and others wrap you uptight like a toasty burrito.
As you sleep, your body heats the air around your body to keep you cozy and warm. If there’s less air space in your sleeping bag, your body can heal it up more efficiently and you will sleep warmer.
Rectangular sleeping bags
The boxy shape is like your bed at home: spacious and comfy. On warm nights, unzip it and use it as a blanket. Rectangular sleeping bags are:
- Bulky to pack
- Less thermally efficient since they have a lot of air space
- Usually used for front-country camping
- Best suited to summer temperatures
Barrel sleeping bags
These are cut a bit closer than rectangular bags so they provide better thermal efficiency. Some may have a hood for extra warmth. Barrel sleeping bags are:
- Moderately roomy
- Moderately priced
- Lighter and more compact than rectangular bags
- Great for both front-country and backcountry camping
- Best suited for summer or three-season use
Mummy sleeping bags
Named for the shape of the coffins Egyptian mummies were found in, and the close cut and integrated hood of mummy bags maximizes their warmth. Mummy bags are:
- Cut close to the body (some people may find this claustrophobic)
- More expensive
- Very light and compact
- Best for backcountry camping
- Best for three-season and winter use
Quilts for camping
These can be a lot more sophisticated than the one you use at home. In general, they’re insulated blankets without any insulation underneath you since you’ll be lying on a sleeping pad. They come in shapes from basic rectangular models to deluxe contoured versions with hoods and straps to attach to your sleeping pad. Quilts are:
- Designed to be draped over the body loosely, or secured to your sleeping pad with straps. Good if you want a less restricted sleep.
- Very light and compact.
- Some types are best for front-country camping while others are great for backpacking use.
- Best for summer or 3-season use, or if you want to save space and weight in your pack.
What size sleeping bag to get?
Most models of sleeping bags come in a few different lengths. The size you choose should match your height plus an extra inch or two. If your bag is a lot longer than you, you’ll have unused space to heat and you’ll feel colder as a result. If your bag is too short, you’ll press up against the hood and foot box, which squishes the insulation and leads to cold spots.
Women’s sleeping bags
These usually come in shorter lengths. They’re designed to fit a woman’s shape with narrower shoulders and wider hips than unisex bags. Sometimes they also have extra insulation in the torso and foot box areas where women tend to feel the cold most.
Kids’ sleeping bags
Kids’ sleeping bags are shorter and narrower than adult bags. They often useless technical fabrics and insulation to keep costs down and boost durability.
Double sleeping bags
Couples who like to snuggle may want to invest in a double sleeping bag, sized to fit two people. You’ll find roomy rectangular drive-up camping versions and ultralight mummy cut double bags designed for lightweight backpackers.
Sleeping bag insulation: down vs. synthetic
Sleeping bags use insulation to trap warm air inside the bag as you sleep, and it’s either made of down or synthetic. Here’s a brief overview:
|Lighter weight||Heavier than down|
|Very compressible||Less compressible|
|Loses warmth when wet||Maintains warmth when wet|
|Stays fluffy longer||Loses their fluffiness sooner|
|Requires careful and specialized washing||Easy to care for|
|Made from down found under the feathers of geese or ducks||Made from polyester derived from petroleum|
Down sleeping bag insulation
Down insulation is made up of thousands of plumules – fluffy filaments from goose or duck feathers. Down fill-power is a good indicator of quality, and higher fill-power provides more warmth for the same weight. About 500 is good, 600–700 is better and above 700 is excellent.
A down sleeping bag is a great long-term investment if you plan to use it a lot. Keep in mind that when down gets wet, it forms clumps and no longer retains warmth. So for extended trips, wet weather, or anywhere that dampness is likely to accumulate, down insulation might not be the best choice.
Synthetic sleeping bag insulation
Synthetic insulation uses polyester threads spun in continuous long filaments mixed with short pieces, called staples. Many bags contain a mix of thinner and thicker pieces, as thinner threads fill empty spaces and trap warm air effectively, while thicker strands provide loft and durability.
The fibers will eventually begin to compress and lose some of their fluffiness over time, so synthetic-fill bags don’t last as long as down bags. However, synthetic sleeping bags are inexpensive, easy to care for, and retain their warmth when wet, so they’re a good choice for damp climates and campers on a budget.
Sleeping bag features
Does your head get cold? Want to zip sleeping bags together? Do you keep sliding off your sleeping pad? Look for these features:
Hood: When it’s cold, keeping your head warm can be crucial. Most 3-season and winter sleeping bags made for backcountry use have hoods that cinch tight to seal in heat.
Draft collar: Also known as yokes, neck baffles or face muffles, the draft collar is an insulated piece around your head and neck that prevents warm air from escaping. Usually on cold weather bags.
Draft tube: An insulated tube that runs along the inside of your sleeping bag’s zipper. Keeps drafts out and warm air in.
Sleeping bags that can zip together: Some sleeping bags can zip together to form a double sleeping bag. It’s a nice option for cuddling couples, but since there will be air gaps at the top, it’s a less efficient way to stay warm. You can zip two sleeping bags together if:
- The zippers are the same type. Sleeping bags from the same brand are the easiest to mate.
- The zippers are the same length. If one bag has a full-length zipper but the other only has a ¾ length zipper, they won’t match up.
- For mummy bags: one bag should have a zipper on the left side and the other should have a zipper on the right side (unless one of you is okay sleeping with a hood over your face).
Sleeping pad sleeves: Some sleeping bags have a sleeve on the bottom to slide your sleeping pad into. Often called a “system sleeping bag,” these bags may have less (or no) insulation on the bottom since the pad is insulated. Sleeping bags with pad sleeves are lighter and more compressible (great for ultralight backpackers).
Sleeping pad straps: Sewn-in straps, often made of stretchy material, to secure your sleeping bag to your pad so you won’t roll off.
Pillow pocket: Some sleeping bags have a sewn-in pouch to hold a small camping pillow. Or just stuff the pocket with a puffy jacket for a DIY pillow.
Once you’ve got your sleeping bag picked out, you may want to check out a few other items for your sleep system:
Sleeping pads provide cushioning and insulate you from the cold, hard ground. All sleeping bag temperature ratings assume you will be using a sleeping pad. Check out how to choose a sleeping pad to find the right one for you.
Your sleeping bag probably comes with a standard stuff sack, but if you plan to transport it in your backpack, canoe, or pannier, you may want a compression stuff sack to save space. When you’re done camping, store your sleeping bag in a big home storage sack so the insulation doesn’t get compressed.
Sleeping bag liners
These can add a couple of degrees of warmth, but most are designed to wick moisture and keep your sleeping bag clean. Bonus: if it’s hot you can sleep in just the liner.