Our calculator provides estimates based on standard material densities and geometric volume calculations. For most shipping purposes, it’s accurate within 5-10%. For critical applications, we recommend verifying with a scale.

Outer dimensions measure the complete exterior size of the box, while inner dimensions measure the available space inside. If you’re using the wall thickness feature, we automatically calculate the difference to provide more accurate weight estimates.

Different materials have different weights for the same volume. Cardboard is lighter than wood, which is lighter than metal. Selecting the correct material ensures your weight estimate accounts for these differences.

Most carriers charge by dimensional weight (size) or actual weight (whichever is greater). Use our calculator to determine both: the physical weight from your materials, and dimensional weight (L×W×H/divisor). Compare both to estimate costs.

This calculator estimates the weight of the empty box itself. To account for contents, you’ll need to add their weight separately. For packing materials like bubble wrap or foam, you can increase the wall thickness slightly to approximate their weight.