Backpack Size Calculator
Enter your torso length, hip size, the number of nights and your kit style. The calculator gives the frame size and the pack volume in litres.
- Backpack size
- Frame
- Volume
Measure from the bony bump at the base of the neck to the top of the hip bones.
Frame size comes from torso length, volume from trip length. An 18.5 in torso is a medium frame. For 2 nights with standard kit you want a 50 to 70 litre pack.
Backpack frame size chart
By torso length. Search for a size.
| Frame | Torso |
|---|---|
| XS | Under 16 in |
| S | 16 to 17.5 in |
| M | 18 to 19.5 in |
| L | 20 to 21.5 in |
| XL | 22 in and over |
Inches.
Nights and volume
Standard kit. Slide the nights.
The pack grows with the trip.
How to choose a backpack size
Body to pack. Step through it.
Torso
Measure it.
Load the pack and walk around the shop before you buy.
Daypack, weekend or expedition
Pack sizes. Compare them.
Day hikes.
1 to 3 nights.
5 nights and more.
Most of the extra space on long trips is food.
Before you buy
Pack checks. Tick each item.
Tick each item as you go.
The hip belt should carry most of the weight.
What you get
Backpack sizing. Each tile explains one result.
Size.
Litres.
Fit.
Nights.
Weight tip.
A pack with the wrong torso length puts the load on your shoulders.
Frequently Asked Questions
No question matches that search.
What size backpack do I need?
Pick the frame from your torso length and the litres from your trip.
How do I measure torso length?
From the bony bump at the base of your neck to the top of your hip bones.
What size backpack for a weekend?
About thirty five to sixty litres for one to three nights.
Is torso length the same as height?
No. Two people the same height can have different torso lengths.
How heavy should my pack be?
Under about twenty percent of your body weight.
Can women use unisex packs?
Yes, but women's packs often fit shorter torsos and curved hips better.
A pack that carries well
Fit the frame to your torso and the litres to your trip and the miles go easier.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.