How Heavy Should My Child’s Backpack Be?

This question comes up every August, and for good reason. A backpack that is too heavy is not just uncomfortable. Over time, it can affect posture, how a child walks, and even how well they focus once they get to their desk.

The General Guideline

A commonly cited rule of thumb is that a child’s loaded backpack should weigh no more than about 10 to 15 percent of their body weight. For a 60 pound child, that works out to roughly 6 to 9 pounds. This is a general guideline rather than a strict medical rule, and it is worth checking with your pediatrician or an occupational therapist if you have specific concerns about your child’s back or posture.

Signs the Backpack Is Too Heavy

A few things tend to give it away. Your child leans forward noticeably to counterbalance the weight while walking. You notice red marks or indentations on their shoulders after they take it off. They complain of back, neck, or shoulder pain, especially after longer school days. Or they consistently sling it over just one shoulder instead of both, which usually means the full weight feels like too much to carry evenly.

Good Heavy Work vs. Bad Heavy Weight

Here is an important distinction. Heavy work, meaning short bursts of carrying, pushing, or pulling during play, is genuinely good for a child’s nervous system. It builds proprioception and helps with regulation. A backpack is a completely different story. It is worn continuously for hours, often loaded unevenly, and carried without a break, which puts strain on developing muscles and joints instead of helping them. The difference is not the weight itself, it is how, how long, and how intentionally that weight is carried.

Practical Tips for Packing Smarter

Always use both straps rather than slinging it over one shoulder. Pack the heaviest items, like textbooks, closest to the back of the bag rather than the front, which keeps the weight closer to the body’s center of gravity. Do a weekly clean-out to remove papers, old snacks, and anything that is not actually needed. If your child’s school allows it, a rolling backpack can be a great option for kids who are carrying an especially heavy daily load.

If you are looking for more general support around your child’s physical development, our page on occupational therapy in San Luis Obispo County covers who we work with and what to expect.

If you have concerns about your child’s posture, strength, or how they are carrying their school load this year, our team at Brainwaves OT is happy to take a look.