How to measure your torso for a backpack, and which packs fit
Same height, different torso, different pack.
Measure from the bump at the base of your neck (C7) down to the top of your hip bones. We'll show packs whose maker's chart says they fit that torso.
Built from the size charts of REI, Osprey and Gregory.
By the Sizemaven team. Rules checked against their sources October 2026.
- 1Torso lengthTilt your head forward: the bump at the base of your neck is C7. With your hands on your hip bones, thumbs pointing back, have a friend measure straight down your spine from C7 to the line between your thumbs.
- 2Hip circumferenceWrap the tape around the tops of your hip bones, on the same line as the torso measurement. That is higher than where your pants sit.
Backpack torso size chart
Size labels from Osprey's and Gregory's own charts; where two labels are listed, either fits. Bands are REI's general ones.
| Torso length | REI band | Osprey Exos (men's) | Osprey Kyte (women's) | Gregory Baltoro |
|---|---|---|---|---|
| 13 in | extra small | Not made | XS/S | Not made |
| 14 in | extra small | Not made | XS/S | Not made |
| 15 in | extra small | Not made | XS/S | Not made |
| 16 in | small | Not made | XS/S or M/L | S |
| 17 in | small | S/M | XS/S or M/L | S |
| 18 in | medium | S/M | M/L | S or M |
| 19 in | medium | S/M or L/XL | M/L | M |
| 20 in | large | S/M or L/XL | M/L | M or L |
| 21 in | large | L/XL | Not made | L |
| 22 in | large | L/XL | Not made | L |
| 23 in | large | L/XL | Not made | Not made |
Questions about backpacks
How do I measure my torso for a backpack?
Tilt your head forward and find the bony bump at the base of your neck, the C7 vertebra. Put your hands on the tops of your hip bones with your thumbs pointing back, and have a friend measure from C7 straight down to the line between your thumbs while you stand up straight. REI describes this method, and Osprey, Gregory and Deuter use the same one.
Is a size small the same across brands?
No. Osprey's men's Exos in S/M fits torsos from 17 to 20 inches, its unisex Hikelite in S/M fits 15 to 19 inches, and Gregory's Baltoro in small fits 16 to 18 inches. That's why the tool checks each pack's own range instead of the letter.
What if I'm between two sizes?
Osprey's chart lists inches where either size fits, for example 19 to 21 inches on the Aether. In that case we show both sizes. A pack with an adjustable harness covers the gap best.
Do I need to measure my hips?
It helps. Measure around the tops of your hip bones, which is higher than your pants waist. REI says hip sizing is rarely off when the torso fits, and most fixed hipbelts cover about 26 to 50 inches.
Can I use my height instead?
Not reliably. REI and Gregory both size packs by torso length, because two people of the same height can have torsos several inches apart.
How we size backpacks
The rule comes from the charts below, checked October 2026. Brands differ, so check the size chart on the product page before you buy. Read our method