Cut foam, don't buy a new lunch box

Cutting a piece of foam to the shape of your container is the fastest way to make any ordinary lunch box fit like it was designed for that specific bottle or snack cup.

Get a thick foam sheet (like the kind used for camping seats or craft foam) and trace the bottom of the container onto it. Cut slightly inside the line, then press the container in — the foam grips it and stops it from sliding around. For tall bottles, cut a block with a hole in the center, or just glue two smaller pieces together as side walls.

No foam? Cardboard wrapped in duct tape works fine for dividers. Measure the inside of the box, cut strips at the right height, and wedge them into place. If you don’t want a permanent setup, use Velcro strips or elastic bands to strap the drink bottle against the inner wall — zero cutting involved.

Just make sure to account for closing the lid. Test the height before you glue anything.

Future you will be glad you spent ten minutes on this instead of overpaying for a “fits everything” bento box.