How do you size a backpack for a woman?

By Dana Okoro, Editorial Director · Updated August 31, 2026

Direct Answer

Size a women's-fit hiking backpack by measuring torso length from the C7 vertebra to the iliac crest, then matching that number to the specific brand's women's size chart rather than its unisex chart. Load the pack and confirm the hipbelt centers on the hip bones and the shoulder straps sit flat with no gap at the collarbone.

a step demonstrating: How do you size a backpack for a woman, hands and gear only, no face

Torso length, not height or clothing size, determines how a women's-fit pack sits on the body, since two hikers of the same height can have torso lengths that differ by two inches or more.

Step-by-step measurement

Tilt the head forward and find the C7 vertebra, the bony bump that protrudes most at the base of the neck.

Place both hands on the hips with thumbs pointing toward the spine to locate the iliac crest, the top of the hip bones.

Have a second person measure straight down the spine with a flexible tape, from the C7 point to the line between the thumbs.

Record the number in inches and compare it against the specific brand's women's chart, since the same measurement can land in a different size tier depending on the manufacturer.

What the number typically means

Torso length	Typical women's-fit size
Under 14 in	Often below standard range; check petite or short-torso sizing
14–15.5 in	Extra-small
15.5–17 in	Small
17–18.5 in	Medium

Chart boundaries shift by half an inch or more between brands, so treat this as a starting point rather than a universal rule.

Confirm the fit under load

Load the pack with a few pounds of gear before judging fit, since an empty pack won't reveal how the hipbelt and straps behave once weight settles in. The hipbelt padding should center directly over the hip bones, not ride up onto the waist or slip down onto the thighs, because a correctly centered hipbelt carries roughly 80% of the total load. Shoulder straps should wrap the shoulder without gapping near the collarbone, and load lifters should sit near a 45-degree angle from the shoulder to the pack body. A hiker who measures between two sizes should size down on a fixed-frame pack or set an adjustable suspension to the middle of its range, then fine-tune after this loaded check.