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How Much Weight Can a Backpack Hold?

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For the well being of your neck, shoulders, back, and hips, here’s something new for you to consider. Whether you have a school-aged child, you’re going camping, or you’re trying to pack a military bag, it’s important to know how much weight can a backpack hold?

The weight a backpack can hold is a lot more than can be comfortably carried. The weight that should be carried in a backpack depends on the person carrying it. A child won’t be able to carry the same amount of weight as an adult. 

Comparing Different Backpacks

School Backpack

Whether it’s kindergarten, middle school, or university, Children’s backpacks are usually made very similarly. Two straps that go over the shoulders, and a couple of large deep pockets to cram as many binders and books as you can carry. 

school backpack

Did you know that you shouldn’t be carrying more than 15% of your body weight in this style of backpack? For a child around 70lbs, they should only be carrying about 10.5lbs in their backpack. That’s only a couple of binders, a pencil case, and a lunch box. 


Hiking Backpack

When you’re hiking, you should be carrying relatively less than a child does. 

hiking backpack

For your hiking trip you’ll need water, and maybe some snacks. You will probably want to bring a camera to take pictures along the way or from the view you’re hiking to.

And to keep you comfortable you might toss in an extra pair of socks or a small first aid kit. 

All of this shouldn’t weigh more than 10% of your body weight. 


Backpacking Pack

Backpacking will require you to carry a lot more than hiking. You’ll need to carry all of your essentials including a tent, a sleeping bag, and food, but there are extra comforts that you should also consider. 

hiking backpack

A fully loaded backpacking pack shouldn’t weigh more than 20% of your body weight, but multiple factors might influence how much your pack weighs. 

  • Trip duration: You’ll need to pack a lot more food and fuel for a week-long trip than you would an overnight trip. 
  • Season and Weather: In cooler temperatures, you will need to stay warmer and will have to carry heavier clothing and gear than in warm summer weather. 
  • Your desire for comfort: While some people might be comfortable sleeping in nothing but a lightweight hammock, you might want the luxury of a bigger tent, a nice sleeping bag, an inflatable pillow, or a folding chair. While you’ll be comfortable while camping, this does add extra weight to your pack. 

Despite how long you go camping for, the weather, or how comfortable you want to be, the weight of your gear should remain around 20% of your body weight, but the size of your pack can be much bigger. 

Weekend (1-3 nights): 30-50L

Multiday (3-5 nights): 50-80L

Extended-trip (5+ nights): 70L+

What this means is you can put more in your bags, but everything you put in will have to be lighter. 

If this sounds like a fun time, check out the complete guide to camping for more information on how to start. 

Military Bag

If you’re in the military packing a bag, you can expect to be required to carry a bag weighing 30%-50% of your body weight. The difference between a military bag and a backpacking pack is the structure of the bag itself. 

military bag

Military bags have lightweight frames made of aluminum to provide support for the bag, with the addition of chest straps and waist straps to redistribute the weight of the bag.

This lowers the center of gravity and makes it easier for the carrier to keep their balance. The weight shift also makes an impact on the joints and it takes longer to become fatigued. 


Summary at a Glance

School BackpackHiking BackpackBackpacking PackMilitary Bag
Suggested Weight Capacity10-15% of carrier’s body weight10% of carrier’s body weight20% of carrier’s body weight30%-50% of carrier’s body weight
How to Calculate Weight Capacity(Carrier’s weight) x .15(Carrier’s weight) x .1(Carrier’s weight) x .2(Carrier’s weight) x .5
How Long Should This Bag be CarriedUp to 1 hourUp to 8 hoursUp to 16 hoursUp to 16 hours with small breaks
Snapshot of how much weight can be carried in each bag.

Effects of Too Much Weight

Carrying too much weight in any of these backpacks can have harmful effects.

Too much weight can cause physical damage to your body. Heavy backpacks can cause excessive strain on the neck, shoulders, back, hips, and knees. This is because your body adapts to the weight by leaning forward to keep balanced. 

Over time this can cause the shoulders and upper back to curve forwards towards the chest. 

Carrying too much weight can also affect your experience. 

If you’re hiking up a steep trail carrying too much weight, you might find yourself more fatigued and irritable. This makes any trip undesirable. 

If you’re backpacking, or in the military and you need to reach checkpoints by dusk, carrying too much weight can severely slow you down. There’s a military rucking rule that says every 1% of your body weight in your pack makes you six seconds slower per mile. 

While this might not sound like a lot, every 1.5lbs on a 150lbs man slows them down 6 seconds per mile. Now imagine the same person carrying a 30lbs backpacking pack.

This slows down the carrier 2 minutes every mile. And the same person carrying a 75lbs military bag? 5 minutes slower per mile. 

With the average mile taking 15-20 minutes unburdened, that’s a pretty big difference. 

What Now?

You’ve measured your bag, and you realize you are carrying way too much? It’s time to cut out anything you don’t need. 

School Backpack

If a student has access to a locker, urge them to use it. By storing all unnecessary binders, notebooks, textbooks, and a lunch bag between each class you can cut out 75%-80% of the weight!

Same thing for returning home. Only bring home the homework you have for the night. 

Hiking Backpack

You probably don’t need as many snacks or camera lenses as you think you might. Unless you’re going to be on the trails all day, you can leave most of your snacks, extra water, spare batteries for your camera, and back up socks in the car or at home. 

The weight you take off will even help you reach your destination faster so you will need less water, snacks, and batteries for your camera anyway. 

Backpacking Pack

Start by knowing your base weight. These are items that have to go with you like your tent, sleeping bag, and cookware that will not change weight over time.

Food, clothes, fuel will need to be added, but you can repack food into smaller and lighter sandwich bags, reduce the number of clothes you will realistically need, and evaluate how much fuel you will need. 

When you get back from a backpacking trip, empty your bag into three piles; things you used every day, items you only used a few times, and things you didn’t touch.

Remember the items you didn’t use and don’t pack them next time (unless it was the first aid kit, you just got lucky on your last camping trip)

Military Bag

Soldiers only carry the extreme necessities; food, ammo, and radios. They will leave all of their comforts back in their duffle bags, and will sometimes even leave their sleeping bags behind to opt for something much lighter like a poncho.

Even things like a change of underwear and an extra pair of socks are an extreme luxury in your bag. 

Wrapping It Up

You might think that the more space you have in a backpack means you should put more things in it. This isn’t the case and can cause major damage to your body, and bad experiences. 

It doesn’t matter if you’re using a school backpack, a camping backpack, or a military backpack, you should always follow the weight capacity guidelines and stop carrying things you don’t need. 

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