Backpack Size Guide: Everything You Need To Know

Want to get a backpack but you aren’t sure how to pick the right size for you? Your troubles have come to an end – this backpack size guide will tell you everything you need to know about backpack sizes!

We’ll guide you through everything, from choosing the right size based on your body shape to calculate the approximate capacity if the manufacturer failed to list the volume of the bag. We’ll also go through the average capacities of basic backpack types, just to give you an idea of what to expect.

So, if you can’t figure out which size is right for you, if you’re having trouble visualizing the size of an 80-liter backpack or if you want to know how to figure out the capacity on your own, you are definitely in the right place!

How Big Is A 20/40/60/80-Liter Backpack?

When you’re looking at different backpacks, you usually see their capacity expressed in liters, and sometimes cubic inches. But, until you’ve actually held the backpack in your hands, it can be pretty difficult to visualize just how big it actually is.

Let’s do it the easy way – I assume you have at least one small, 18-20” suitcase. The capacity of those is usually around 35-40 liters (up to 2441 cubic inches), which is pretty much the same capacity you get in a standard 22” carry on backpack.

So, a 20-liter backpack can hold as much stuff as a single compartment of the suitcase, while an 80-liter backpack could hold twice as many items as the entire suitcase.

Backpacks are a lot bigger than they seem, especially the ones that have lots of external pockets and multiple compartments. That’s another thing people often forget about – the capacity of every single pocket is included in the total capacity of the backpack.

So, if you want a bag with a massive main compartment, you should definitely look for something that doesn’t have too many outer pockets, since those bags can ultimately fit fewer items inside their main compartments.

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