How Many Units Per Box

"How many units fit in this box?" is the question every seller asks before a shipment. The honest answer is: it depends on orientation, and a single formula rarely gets it right.

The Naive Formula

For one product in one orientation:

units = floor(box_L / product_L) * floor(box_H / product_H) * floor(box_D / product_D)

This undercounts whenever rotating the product, or combining orientations, would use the leftover space.

Why Orientation Changes Everything

A product that is 12 x 8 x 5 cm can be placed six different ways. In a given box, one rotation may waste 4 cm of height while another fits a whole extra layer. Testing all 6 rotations is the difference between a tight pack and shipping air.

Simulating in 3D

A 3D simulation does three things a formula cannot:

• Tests every rotation per item
• Fills the gaps left after the main stack
• Shows the layout so you can verify it visually

FAQ

Why does the calculator show more units than my hand estimate? Because it tests all orientations and fills leftover gaps, not just one grid layout.

Can I include packaging in the calculation? Yes. Enter packaging thickness in millimeters and the packed size is used instead of the bare product size.

Does it work with mixed products? Yes. You can add several products with quantities and BoxOptimizer packs them together, returning units placed, weight, free space, and cost per unit.