Calculation method

This calculator uses the following planning method:

Internal dimension = product dimension + 2 × (clearance + wrap thickness)

Worked example

A 10 × 6 × 4 in product with 0.5 in clearance and 0.25 in wrap on every side needs at least 11.5 × 7.5 × 5.5 in internally.

How to interpret the result

Round each result up to an available internal box size. Check the manufacturer’s internal dimensions, not only the external carton label.

Assumptions and limitations

This is a rectangular fit estimate. Compressible, irregular, fragile, or orientation-sensitive products need a physical pack test.

Estimate only. Verify the packed result with actual materials and the current requirements of your supplier, marketplace, or carrier.

Last reviewed: July 26, 2026