boxmetric.

PARCEL MATH · WITHOUT THE GUESSWORK

A big box can
weigh more.

Compare scale weight with volumetric weight. Enter your carrier’s divisor and rounding increment to see the larger, rounded weight for one parcel.

Free calculatorNo accountYour inputs stay here
1

Measure the packed parcel

Outside dimensions

Use the packed outer dimensions, including bulges. Apply any carrier-required dimension rounding before entry.

Scale weight
Your carrier’s rules

5,000 and 0.5 kg are illustrative defaults, not a carrier quote. The divisor always uses cm³/kg, even when you enter inches or pounds.

THREE CHECKS BEFORE YOU BOOK

Measure outside.

Packaging counts. Use the final parcel dimensions and scale weight, rather than the dimensions of the item inside.

Bring the rule.

Divisors and rounding steps differ. Take them from your actual service’s current published instructions.

Compare fairly.

The calculator converts all dimensions to centimetres, computes volumetric kilograms, then compares both weights in your chosen unit.