Are you interested in choosing the right sleeping bag? That’s not a big deal. Stick with me and find your dream sleeping bag.

The world of camping sleeping bags can be a daunting one. There are so many choices and variations that it’s hard to know what size bag you need. Size is a critical factor because the temperature rating of a sleeping bag is only applicable to people who fit within that bag comfortably!

Key Measurements To Consider

  1. Shoulder Girth or Width: This is the circumference of your shoulders, usually taken at the widest point of your chest.
  1. Hip Circumference: The circumference at your hips, this measurement will be important for determining how much loft a sleeping bag has.
  1. Length of Back: A person’s back length should be used as the basis for choosing a sleeping bag. A person who has a shorter back doesn’t need to have a mummy bag since their head will stick out of the top.

Materials To Consider

Sleeping Bag padding is very important; most people will choose down sleeping bag or synthetic insulation for this reason. Down is the best quality insulation available. 

It is lightweight, warm and easily compressed. On the downside, it loses all of these qualities when wet and dries very slowly; Synthetic insulation is a lot better in this respect.

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Temperature Ratings

A sleeping bag temperature ratings is only approximated based on how people with the average body heat feel in that bag!

You can do this by experimentally determining your comfort limit and choosing a sleeping bag that would keep you warm well beyond that temperature if you were in it right now.

The basic rule of thumb used to determine the temperature rating is: “If you sleep cold, get a warmer bag; If you sleep hot, get a cooler one.”

When choosing a sleeping bag, make sure you know your size and find the right sleeping bag for the season.

Sleeping Bag Size Guide

Shoulder girth: ____ inches

Hip circumference: _____ inches

Back length (for rectangular bags): _______ inches

A well-made and fitted sleeping bag will be a pleasure to sleep in on cold nights, but a poorly made one could make your camping trip uncomfortable.

The most important measurements are shoulder width, hip circumference and back length. The shoulder width should be larger than your widest point, which is usually around the shoulders.

Hip measurement will help you get a sense of how big the bag is and whether it can accommodate layers of clothing to keep you warm in cold weather; In addition, the sleeping bag’s footbox should accommodate your feet with room to spare

Sleeping Bag Choices

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Rectangular Sleeping Bags

The traditional mummy sleeping bags bags are great for keeping you warm, but they’re more constricting. In colder conditions, this is not much of a problem, but a rectangular bag will be more comfortable as a general rule.

Mummy Sleeping Bags

The mummy sleeping bag are much more thermally efficient than the traditional ones. They’re also lighter and smaller; this can be an advantage or a disadvantage depending on your camping conditions.

Sleeping Bag Pads

 The pads provide insulation below you and also keep you from sleeping directly on the cold ground. They’re often inflatable, allowing for a customizable level of firmness.

Sleeping Bags With Liners

A liner will add some warmth to your bag; it’s much warmer than nothing at all but not as warm as an insulated pad.

Double Sleeping Bags

The double women’s sleeping bags are, as the name suggests, extra roomy and warm. If you’re a cold sleeper or you want to share your bag with a friend, this is the way to go.

Sleeping Bag Fill Power

This term refers to the quality of down insulation and should be considered when comparing two models side by side. The higher the number, the “fluffier” and more insulating the bag are likely to be.

Sleeping Bag Zippers

 A good sleeping bag will have two zippers; this allows you to open up a vent if you’re too hot or close it if you get cold. Some designs also let one person open the bag up completely.

Sleeping Bag Hoods

 This is where insulation is added around your head and face. The hood also helps lock in the warmth by covering your head.

Why Sleeping Bag Fit Is Necessary

An accurate fit is necessary for your warmth, safety and comfort.


In cold conditions, being uncomfortable can lead you to start shivering uncontrollably.

This triggers a “survival reflex” that causes blood vessels in your arms and legs to constrict; this reduces the flow of warm blood through these vessels, so less heat reaches your extremities.

In a well-fitted sleeping bag, the insulation should be able to trap enough of your body heat, so you don’t start shivering. If there are gaps in the insulation, warmth can escape and expose you to cold temperatures.


A loose or ill-fitting sleeping bag can be dangerous if it bunches up when you move around; this can cause the insulation to shift and expose you to the cold. Also, make sure your sleeping bag is long enough, so it doesn’t ride up over your face when you sleep.


The bag should fit snugly but not be too tight. If there are gaps in the insulation or loose material, your movements will cause it to shift, which reduces its effectiveness.

Tips For Sleeping Bag Fit

Check the bag’s sizing chart for shoulder girth, hip circumference and back length measurements before you buy or rent one.

Try out the backpacking sleeping bag at home, especially if there’s a chance that you’ll need to return it.

If you can’t return the sleeping bag, take advantage of trial periods offered by outdoor 

equipment companies; these vary in length but allow you to test out the bag in your backyard or tent.

Final Words

The best sleeping bag size for you is according to your weight and camping conditions. You can find a wide variety of sleeping bag sizes to choose from at REI and Campmor.

Make sure you know your sleeping bag shape, size and find the right backpacking sleeping bags for the season.


How big should my sleeping bag be for winter camping?

It depends on how cold it gets at night. Generally, the more room you have in your sleeping bag and the more layers of insulation you use, the warmer you’ll stay. Also, consider what equipment you’re using; if it’s a bulky mummy-style bag, it may warm you up less because of the restricted space.

How should my sleeping bag fit?

 A well-fitting bag should be long enough to cover your face and keep your head warm, but not so loose that it drags on the ground when you move around.

What is a mummy-style sleeping bag?

This type of bag is tapered around the feet to create a more customized fit and also reduce dead space, which is air trapped between your body and the insulation.

The mummy design often reduces weight because it has less material than other styles. Cleaning this style may be harder as well since the tapered end will need to straighten out to ensure the zipper’s full length is accessible.

How do I select the size?

You can select the size by measuring your height and weight. You can contact outdoor equipment retailer REI & Campmor for more information about sleeping bag sizing and fit.