Knowing how to fit a backpack properly is half the battle when it comes to choosing the right one for you. There are plenty of misconceptions flying around about how to measure a backpack for your size. When you’re hiking for extended periods of time, you’ll soon know if you haven’t sized your backpack properly.

Although heavy, backpacks should remain comfortable. If you have chosen the right size, a backpack should make the overall weight feel much lighter and manageable. If it is wrong, though, you’ll feel it weighing down on your shoulders, digging into your hips, and sore on your back.

In this guide, we’re going to cover the various ways you can fit a backpack so that you’re confident in choosing the best one for you.

Backpack Fitting is All About the Torso Size

Many people wrongly believe that a backpack size is based on your overall height. This isn’t true, it is actually primarily based on the length of your torso. When you base the size on your torso length, you can then ensure that everything is in the right place i.e. the hip belt on your hips and so on.

In order to measure your torso correctly, have a friend help you out and follow the next steps:

• Find your C7 vertebra (this the upper most ‘lump’ at the top of your spine, easily found by tilting your head forwards)
• Locate the top of your hip bone (easily felt by running your hand down your side)
• Measure down your spine the distance from your C7 to height of the top of your hips
• Note this number as it will be what you use to pick your backpack

You should keep in mind that fits can vary slightly between brands, so it is always worth trying them out in person if you can. Furthermore, if you’re between sizes then some bags come with adjustable straps which will allow it to fit better.

Making it More Comfortable

Although the primary sizing factor is based on your torso length, it doesn’t mean that you’ll have the comfiest backpack straight away. There are some other additional steps you can take to adjust it for maximum comfort, making sure to test it out with a realistic load.

• Over 75% of the weight of the backpack should be carried on your hips
• Make sure the hip strap sits around your hips, not above
• Shoulder straps should lie flat against your shoulders
• Your shoulders shouldn’t carry that much weight but you should be able to feel the straps
• Load-lifters attach your shoulder straps to your pack and should be adjusted to a 45-degree angle
• Your sternum strap should sit mid-chest, making sure not to have it too tight