Packaging decisions for US home-based sellers

How we research

Free calculator

Void Fill Volume Calculator

Estimate unused space in a box so you can plan paper, air pillows, or foam.

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Calculate

Estimates only. Confirm figures against invoices and the carrier’s current rules.

Enter inside box dimensions and packed-product dimensions in inches.

Enter inside box and product dimensions to estimate unused volume.

What this calculator answers

How much unused space is left after the product sits in the box?

Formula

Void (cu in) = (box L × W × H) − (product L × W × H). Divide by 1,728 for cubic feet.

Limitations

Ignores irregular shapes. Does not output bag counts.

Related decisions

Void fill guide for material choice. Tighten the carton with box size, then add unit cost in packaging cost.