For a snack, you need a snack box, not a lunch box

For a small snack, a full lunch box is overkill—you want a compact bento or a soft-sided container that actually fits in a pocket.

Tiny bento boxes exist, but a lot of them are still clunky once you add the latch and the divider. The ones worth carrying are flat and slim: think under 500 ml, roughly the size of a large sandwich. Something like the LunchBots CuBox or a small silicone bag like the Stasher works way better in a coat pocket than any traditional bento. A silicone bag collapses as you eat, which is great.

If you really want hard sides, look for a box around 5 x 3 x 2 inches. That size fits a decent coat pocket but still holds a decent snack—not a meal. Don’t trust dimensions from product photos; check the actual measurements before buying.

Don’t buy a lunch box until you realize you’re packing a granola bar and a few grapes.