Blue Planet Kids dot Com
Products you select will be placed in your Shopping Crate
Search Products:
Go Shopping!

                         How To Fit Your Backpack Properly

When you buy a backpack, it’s important to get one that fits your body. With any luck – you’ll be spending a lot of time on the trail, and you need a pack that will carry a load without creating its own set of problems. To accomplish that, begin by choosing a pack that is sized for your body.

The size and fit of a backpack is based on your torso length – not your height or weight. Don’t assume that torso length is related to height. Did you know that a person who is 5’6” can have a longer torso than someone who is 6’0”? It’s true. Tall people don’t necessarily require large packs. So go find that measuring tape (look in the kitchen drawer) and let’s get to work…  

Measuring Your Torso: You can try to do this by yourself, but it’s much easier if you have someone help. If you don’t have tape measure, use a non-stretchable string then measure the string with a ruler. 

Start by locating your 7th vertebrae. Just bend your head forward and find the bony bump located between your shoulders - at the point where your neck meets your back. That’s your 7th vertebrae.

Now, place your hands on your hips (not on your waist), directly on the peak of your hipbones (also known as the iliac crest), with your thumbs on the back of your torso – pointing toward the base of your spine. This part of your torso will be circled by the pack’s belt. This allows your hipbones to support the pack’s belt and some of the load.  

Place the end of the tape measure on the 7th vertebrae and guide the tape down your spine following the contour of your back to the imaginary line between your thumbs. The length from your 7th vertebrae to an invisible line between your iliac crests is your torso length.

Backpack Sizes: Backpacks typically come in three frame sizes, Small, Medium, and Large. Your torso length should fall into one of those size ranges:

  • Youth: 12” to 16”
  • Small: 16” to 18"
  • Medium/Regular: 18" to 19 1/2"
  • Large/Tall: 20" and up

Be sure to check the size range on the packs you are considering. If you are considering a pack with interchangeable belts, you should also measure the distance below your waist, around your iliac crest.

After you have chosen the correct torso size, it's time to tailor the pack to your individual body shape. 

Suspension Adjustments:
When your pack arrives,  try it on to make sure that the torso size is correct and adjust the suspension systems and tailor the fit to your specific needs. High quality packs have suspension systems designed to support and distribute the load and increase your comfort. Familiarize your self with these systems because you may wish to adjust them when you carry different loads, etc. 

Load the pack with about 25 pounds of weight. You can use anything that won’t mess up the pack. Bags of rice (uncooked, please), your little brother, your sleeping bag or folded sheets will simulate a load. Now, put the pack on by slipping your arms through the shoulder straps and check these points of fit.

Hipbelt: Position the hipbelt around your hipbones or iliac crest, close the buckle and pull the strap to make the belt snug but NOT tight. The weight of the pack should be resting on your hips. Be careful not to fasten the belt too high (around your waist) or too low (below the iliac crest). Placing the belt too high will cause the load to pull on your waist and stomach. Placing the belt too low will put too much weight on your shoulders and back. Cinch the shoulder straps by pulling down on the tensioning strap - then release the tension a little bit.

Shoulder Straps: Now check the position of the pack and shoulder straps. On internal-frame packs, the straps should wrap around the top of your shoulders and attach to the pack at a point that is roughly level with our old friend - the 7th vertebrae. The pack should fit closely to you body. External frame packs with load lifting systems should fit in the same way, except there will be a gap between your spine and the pack. If you have an external frame pack without a load support systems, the straps will attach to the pack at a point about one inch above the top of your shoulders. The straps should be placed far enough apart that they don't squeeze your neck, but not so far apart that they are constantly slipping off your shoulder. If the pack has a sternum strap, adjust and close it, then check for comfort.

Load Lifter Straps: These are the smaller straps that are part of the larger shoulder straps. They should be attached to your shoulder straps at a point just slightly below the top of your shoulder. From there, they run back and attach to the pack/frame at approximately a 45 degree angle. If that angle is less than 40 degrees, then too much weight will rest on your shoulders. More than 50 degrees, and the torso length/frame size of the pack is too long.

Now, go jump around a bit. Bend over. Sit down and get up again. Run in place. Pat your dog.

How does the pack feel? Are there chafing points? If it is an internal frame pack, does it move with your body? Can you move your arms and head freely? If it is an external frame, does it place the load on you hips, can you move without rubbing against the frame?

Generally, if the pack fits, you’ll know. If there are significant issues that can’t be resolved by refining the adjustment or suspension, you should return the pack and try a different size or make. Remember, if you have any questions please email us at  We're always happy to help you.

  1. The Complete Guide to Selecting and Fitting the Proper Backpack
  2. Different Types of Packs for Different Uses
  3. Backpack Capacity
  4. Fitting a Backpack

Blue Planet Kids · 7125 Sleepy Hollow Circle · Tallahassee, FL 32312 USA ·
Toll Free: 1-888-880-0708
Contact Us · Return Policy · Privacy Policy proudly uses Verisign to secure all credit card transactions.