Torso length, not height or clothing size, determines how a women's-specific pack fits, since two women of the same height can have torso lengths that differ by several inches.

Step-by-step measurement

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

  • Place your hands on your hips with thumbs pointing toward your spine to find the iliac crest, the top of the hip bones.

  • Have another person measure straight down your spine with a flexible tape, from the C7 point to the imaginary line across your thumbs.

  • Record the number in inches and compare it to the brand's size chart before choosing a size.

    • What the number means

    Torso lengthTypical size
    Under 14 inOften below standard women's range; check XS or petite-specific sizing
    14–16 inExtra-small
    16–17.5 inSmall
    17.5–19 inMedium

    Ranges vary by half an inch or more between brands, so treat this table as a starting point, not a universal chart.

    After sizing, confirm fit under load

    Load the pack with a few pounds of gear and put it on. The hipbelt padding should center over the hip bones, not ride above them onto the waist or below them onto the thighs. Shoulder straps should wrap the shoulder without gapping at the collarbone, and load lifters should run at roughly a 45-degree angle from the shoulder to the pack body. A hiker between two sizes on the chart should size down if the pack has an adjustable suspension, since it's easier to lengthen a strap than to shorten a frame that's built too long.