A Fool-Proof Guide to Buying a Sleeping Bag

The sun falls below the horizon, the air turns crisp, and the stars begin to illuminate the sky. You climb into your tent and snuggle into your cozy cocoon of a sleeping bag, dreaming of the expansive valleys and roaring rivers surrounding you. Sleeping under the stars is one of the camping’s life’s simplest pleasures, but without the right equipment it can quickly turn a peaceful evening into a truly miserable night. Sleep can make or break a day in the great outdoors, so we put together a guide to make sure you’ve got the perfect sleeping bag for whatever you’re up to.

How cold will it be?

Temperature Ratings

There are three overall categories of of sleeping bags: summer, 3-season, and winter. Summer sleeping bags are 35°F and higher, 3-season bags range from 10°F to 35°F, and winter bags are below 10°F. The temperature rating traditionally reflects the lowest temperature which the bag will keep the average person warm. However, manufacturer’s ratings vary greatly so it can be hard to get a good read—one manufacturer’s 25°F can feel like another’s 15°F To get a more accurate and standardized comparison, look at the EN rating.

EN Ratings

The EN rating is a European standard that includes four categories and assumes the sleeper is wearing one layer of synthetic long underwear and is using a sleeping pad and tent.

• Upper limit: the highest temperature at which a standard male can sleep comfortably.
• Comfort: the lowest temperature at which the average woman can sleep comfortably.
• Lower limit: the lowest temperature at which the average man can sleep comfortably.
• Extreme: essentially a survival rating—the minimum temperature at which the average female can remain for six hours without risking hypothermia.

Depending on whether you run hot or cold, it’s usually better to buy a sleeping bag that’s rated to a temperature slightly colder than you’ll actually be camping at.

Type of insulation

Down

It’s hard to beat down insulation when it comes to a high warmth-to-weight ratio. Filled with feathers from geese or ducks, down sleeping bags are generally the lightest and most compressible. Down retains its loft longer than synthetic insulation, with fill power ratings from 600 to 900. Just like your favorite puffy jacket, the higher the fill power, the warmer the bag.

One of the largest drawbacks to down is that it loses its insulating properties when it gets wet and can take a long time to dry. Down is a great choice for lightweight backpacking, or camping in any cold and dry climates. It is also usually more expensive than synthetic insulation.

Synthetic

Synthetic bags offer a high level of durability and are usually filled with some sort of polyester. A synthetic construction really shines in wet climates, retaining its insulating properties even when wet and drying quickly if you do get soaked. A synthetic bag is definitely the way to go if you’ll be camping on snow—all it takes is one frigid night huddling in a soaking wet down sleeping bag to invest in a synthetic option. They also generally come at a lower price point, making them a popular choice among budget-friendly campers.

One of the major downsides to a synthetic bag is that they are usually much heavier and bulkier than down, making it tough to tote along on a multi-day backpacking trip. Some synthetic bags can be packed down pretty small, but synthetic insulation gradually loses its warmth the more it is compressed.

Features to consider

Shape

Mummy bags and rectangular bags are A mummy bag tapers towards the feet and fits snugly around the body. Mummy bags maximize thermal efficiency and are usually much more compressible than a rectangular bag. Rectangular bags don’t retain heat quite as well but give you a little more movement to wiggle around. They are more suitable for summer car camping and caravanning.

Draft collar

An insulated flap of insulation around the neck of your sleeping bag that prevents heat from escaping. The draft collar is more important in winter bags and essentially helps to seal you off from the cold air outside.

Zippers

Most sleeping bags have either a left or a right zipper. Summer bags usually have a full-length zipper for easy ventilation in the summer, while winter bags usually don’t go down all the way. Try out the zipper before you make your purchase to make sure it doesn’t snag too easily. It can be really frustrating to try and get out to pee in the middle of the night, only to be thwarted by a stubborn zipper that won’t slide smoothly.

Stash pocket

Sleeping bags often have a small zippered pocket on the inside or the outside. It can be a great place to stash a headlamp or a spare set of earplugs in case your tent mate starts to saw logs in the middle of the night.

Women-specific design

Women-specific sleeping bags are generally a little shorter than men’s. They fit slightly wider at the hips, narrower at the shoulders, and often include extra insulation in the upper body.

Hood

Having a cinchable hood comes in handy for camping in cold weather. An insulated hood reduces heat loss from your head and often has a pocket to slide a bundle of jackets inside for a makeshift pillow.

Baffles

Baffles are interior chambers found in down sleeping bags that holds the insulation in place. This keeps feathers from bunching up in one area while you’re tossing and turning.

Stuff sack

Most sleeping bags come with a stuff sack that lets you compress your sleeping bag into a smaller compartment for easy transport. When you’re not out hiking, it’s best to leave it in the larger storage sack to maintain the longevity of the insulation.

Buying Tips

If you have the option, head into a gear shop and try it out before you buy it. Most retailers will let you hop inside and roll around in it before making a purchase. Comfort is key when you’re spending the night outside, and you’ll be glad you took a little extra time to dial in the right equipment when you cozy into your mountain cocoon after a long day of walking in the woods.