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Box calculator

Box Size Calculator

Turn product dimensions into a practical internal box size by adding cushioning or clearance. Set one padding value for every side or tune each axis.

Live calculator

Calculate a padded package size

CALCULATES LOCALLY · NO UPLOAD
Clearance / padding per side
FORMULA
Internal box = Product + (2 × padding per axis)

External estimate adds two wall thicknesses per axis.

SUGGESTED INTERNAL SIZE-
External package estimate-
Internal volume-
Added clearance volume-
Confirm the carton manufacturer’s internal dimensions and pack a physical sample before ordering production quantities.
Method

How this calculation works

Internal dimensions describe usable space. Corrugated board thickness must be added separately to estimate external dimensions. ParcelCal runs the calculation in your browser; no package or shipment information is uploaded.

FORMULA
Internal box dimension = Product dimension + (2 × padding per side)

Internal dimensions describe usable space. Corrugated board thickness must be added separately to estimate external dimensions.

Worked example

Two inches of cushioning

  1. 1.Product: 12 × 8 × 5 in
  2. 2.Padding: 2 in on every side
  3. 3.Add 4 in to each product axis

Suggested internal box size: 16 × 12 × 9 in.