How We Fit and Size Your Pack - Outdoor Sports Center

How We Fit and Size Your Pack

Backpacking and hiking are great ways to get out and enjoy the outdoors. The backcountry is full of beautiful scenery and new places to explore. If you want to have a great experience out in the wilderness, a comfortable backpack that fits well should be the first item on your list. Your pack will carry your water, food, extra clothing, a tent, camera, emergency gear and everything else you might need on your adventure.

Finding the Right Frame Size

Sizing your pack is the key to not only comfort but the pack's performance. Making sure your backpack is the correct size for your body will make a tremendous difference over the long haul. A comfortable pack that with a good fit will put the majority of your backpack's weight (about 80%) on your hips, not your shoulders. In order for that to happen, the backpack has to be the right size and adjusted in all the right ways to your body.

Your torso size is the most important measurement and is what determines your pack size. People of the same height many times have different torso, hip and shoulder measurements. Most of our packs are available in multiple sizes to fit a range of torso lengths.  Your torso measurement is the length of your back along the spine from the C7 vertebrae to your iliac crest. The C7 vertebrae is the knobby bone at the base of your neck when you put your head down. The iliac crest is the top of your hipbones on the side of your body that act like a shelf. The distance between the two determines your pack size, if you are in between two sizes our fitters will see which size fits better or if you need to try a different brand or style.


General Frame Sizes

  • Extra Small: Fits torsos up to 16 inches / 41 cm
  • Small/Short: Fits torsos 16 - 19 inches / 41 - 48 cm
  • Medium/Regular: Fits torsos 18 - 21 inches / 46 - 53 cm 
  • Large/Tall: Fits torsos 20 - 23 inches / 51 - 58 cm
  • Extra Large: Fits torsos 22 - 25 inches / 56 - 53 cm 

Sizing the Hip Belt

To figure out what hip belt works for you, measure around your hips at your iliac crest (this is not where you measure for pant sizing). A hip belt that fits well will sit centered over the hipbones and wrap tightly to hold the pack's weight. The ends of the hip belt pads should extent at least 3 inches past your hip crest and about 3 to 6 inches apart when they are tightened down around you. Some back packs have hip belts that are sized and can be swapped out if we determine you need a different size. Certain Osprey hip belts can even be custom molded to your body by a pack fitter.


General Hip Belt Sizes

  • Extra Small: Fits hips up to 28 inches / 69 cm
  • Small/Short: Fits hips 27 - 31 inches / 69 - 79 cm
  • Medium/Regular: Fits hips 30 - 34 inches / 76 - 86 cm 
  • Large/Tall: Fits hips 33 - 37 inches / 84 - 94 cm
  • Extra Large: Fits hips over 36 inches / 91 cm 

Sizing the Harness

Osprey is one of the few manufacturers that offers a fully custom fitting pack where you can swap out the harness of the pack to fit you perfectly. If your harness fits you well it should end 2 to 3 inches beneath your armpit. The harness straps shouldn't be touching your body to prevent rubbing while on the trail. The shoulder pads should wrap around your shoulders with no gaps, or the harness may need to be swapped out.


After figuring out your torso measurement and your pack size our knowledgeable staff will then fit the pack. Pack fitting is the most important part of your pack purchase and unfortunately the aspect that is most often overlooked. Every pack manufacturer always recommends that you get fit for the right pack by a professional at a specialty retailer because fit is the most important part of your pack being comfortable and correctly handling your load. There is rarely a customer that we cannot fit perfectly even if we have to swap out hip belts or harness straps. 

Once you have the correct size pack, harness and hip belt, it's time to correctly put it on and fine-tune the fit. Even though we have the right pack size, it still may not be adjusted properly to your body. First we need to put some weight in the pack (20 to 30 pounds of well distributed weight will do). Then following steps are used to adjust the backpack once it is packed and ready to hit the trail to ensure optimal comfort and performance. In a good fit, there should be no pressure points and also no gaps between your body and the pack. You may want to practice this procedure prior to heading out in order to achieve the perfect fit. Remember, comfort isn't just a luxury when backpacking. If your pack doesn't fit correctly, it could result in injury.

Step 1: Hip belt

Make sure all the pack's compression straps are tightened and the shoulder harness, sternum straps, load lifter straps and hip belt are loosened. We recommend you loosen these straps every time you take your pack off. Buckle and snug down the hip belt with it centered over the hip bones. The padded portion should wrap well around the front of your hips. Fine-tuning of the angle of flare can be done by adjusting the angle where the belt comes out the front of the padding.  Most women require slightly more of an angle where the belt sits on the hips.


Step 2: Shoulder Harness

Tighten the shoulder harness by pulling the ends of the shoulder straps. When tightening these straps, be sure to pull down and behind you.  Your arms should be pointing towards the back pockets of your pants as you pull. This brings your pack closer to your body, and carries a small portion of the weight. Your shoulder straps should completely wrap around your shoulders, with no gap between your shoulder blades and the shoulder harness. The connection points of your shoulder harness to the pack should begin about 2" below your C7 or the top of your shoulders. For packs with an adjustable torso harness break the hoop & loop connection to achieve this fit.


Step 3: Sternum Strap

Buckle the sternum strap and comfortably adjust the position to about 2 inches below your collarbones and lightly cinch it down. This pulls the shoulder straps comfortably away from your armpit and centers them over your shoulders. Do not pull so tight that it hinders your breathing.

Step 4: Load Lifter Straps

Tighten the load lifter straps to draw the load solidly against your back, and taking pressure off the shoulder straps. The lift straps should come off your shoulders at a 45 to 60 degree angle in our larger volume packs that carry a greater weight. In smaller models these straps serve more as compression straps and ride flatter; they may even angle downwards. If a gap forms between the shoulder harness above your shoulders, you will need to tighten the lower shoulder straps more before tightening the load lifters.


Step 5: Go On Your Next Adventure!

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