Get a soft lunch pack, not a hard box

The best lunch box for a backpack is a soft, insulated flat pack that you slide in like a book.

Hard bento boxes are fine for desk days, but they eat into backpack space and don’t flex when the bag is already full. A soft, insulated pack—something like the Fitpack or PackIt—lays flat against the back panel or fits in a laptop sleeve. It takes up about as much room as a notebook, and nothing pokes into your laptop or books.

Look for one around the size of a 13-inch laptop. That size slides into the main compartment without bulging, and you can still fit a water bottle and a jacket on top. Skip anything with a hard shell or a thick insulated wall—the whole point is to pack it flat.

Your future self will appreciate not having to shove a lunch box into an already full bag.