Measuring backpack torso size correctly is one of the most critical items on your pre-trip checklist. If you do it right, your pack will be significantly more comfortable. Furthermore, please be sure to read the “Geek Tips” at the bottom of this article in order to avoid the most common mistakes.

Step by Step Backpack Torso Size Instructions

The first thing you need for measuring backpack torso size is a friend or partner and a flexible tape measure.

  • While standing upright with your chin touching your chest, have your friend locate your C7 vertebra. This is the most protruding vertebra at the base of your neck. This spot should stick out a bit more than the rest of your vertebra and it’s where the slope of your shoulders meets your neck. Your measurement will start from this point (your C7).
  • Place your thumbs on top of your hip bones. Rotate your hands so your index fingers make a straight line across your back (while keeping your thumbs on top of your hip bones). This imaginary line from the top of your hip bones around your back is the end point of your torso measurement and is known as the iliac crest.
  • Stand up nice and straight and have your friend measure the length from your C7 to your iliac crest

With the result of your measurements, use the sizing information just below to select your pack size.

Sizing Information

  • Extra Small: 14 & 15 inches (women’s only for Gregory Packs, Unisex for Deuter Packs)
  • Small: 16 & 17 inches
  • Medium: 18 & 19 inches
  • Large: 20 & 22 inches

Geek Tips

  • Our instructions say to use a flexible tape measure, but the truth is we use a string around Outdoors Geek. Just put a knot in one side and line it up with the C7. Run the string down to the iliac crest and measure the string length with any ruler or tape measure.
  • The C7 also is very close to the collar of most T-shirts after putting your chin on your chest.
  • You will notice there is not a “one-half inch” measurements in our sizing information. Always, always, go with the smaller torso pack when in doubt or if between sizes. This is because a pack with too long of a torso measurement will not properly carry weight on your hips.
  • I’m 5’8″ tall. My torso length is almost 18″ and I have a longer torso than many people my height. My best pack fit is a small torso. If you are 5’8″ and you measured yourself as a 21″ torso, try again. Something was measured wrong.
  • I’ve measured men who are 6’2″ tall who fit a small torso pack. I’ve also measured men who are 6’2″ with large torsos. There is a correlation between height and torso size, but there is not always a direct relationship.
  • If you’re struggling, give us a call at (303)699-6944 and we will help you out.

You can check out Outdoors Geek backpacking gear at this link. Or, for more information and checklists, check out our Geek Advice Page.