About this calculator

Estimate the expanded filling volume remaining around contents inside rectangular cartons. Enter occupied contents volume on the same basis as the carton cavity, then apply your allowance and usable volume per fill pack.

Inputs

How to use this calculator

Packed carton group

  1. Internal carton length (in)Use usable inside dimensions, not outside shipping measurements.
  2. Internal carton width (in)Account for inserts or obstructions separately.
  3. Internal carton height (in)Use measured usable height.
  4. Occupied contents volume (in³)Actual volume excluded from filling, including any inserts. Do not blindly sum overlapping product bounding boxes.
  5. Identical cartonsA whole non-negative count.

Shared inputs

  1. Additional allowance (%)Applied to the calculated total. This is an editable example, not a material performance standard.
  2. Usable expanded fill volume per pack (in³)Enter verified usable expanded volume, not compressed shipping volume. No paper, foam or air yield is assumed.

Enter the shipment or scenario values, then select Calculate result.

Method

Formula and variables

Void per carton = internal length × width × height − occupied contents volume. Sum void × carton count. Required expanded fill = total void × (1 + additional allowance ÷ 100). Packs by volume = ceil(required fill ÷ usable expanded volume per pack).

Internal carton length (in)
Use usable inside dimensions, not outside shipping measurements.
Internal carton width (in)
Account for inserts or obstructions separately.
Internal carton height (in)
Use measured usable height.
Occupied contents volume (in³)
Actual volume excluded from filling, including any inserts. Do not blindly sum overlapping product bounding boxes.
Identical cartons
A whole non-negative count.
Additional allowance (%)
Applied to the calculated total. This is an editable example, not a material performance standard.
Usable expanded fill volume per pack (in³)
Enter verified usable expanded volume, not compressed shipping volume. No paper, foam or air yield is assumed.

Interpret the result

Pack count rounds required expanded volume upward to whole packs. It is a volume-based minimum and does not establish cushioning performance or actual material yield.

Outputs: Total void volume and volume-based pack requirement

A volume balance only. Contents volume cannot exceed the cavity. Geometry, cushioning performance, compression, migration and actual expansion/yield are not predicted. The pack result is a volume-based planning minimum; confirm material yield with the supplier.

Worked example

Check the arithmetic

This example uses the starting values shown above. The arithmetic below is calculated independently of the interactive result.

Work through the calculation

  1. Carton cavity = 12 × 10 × 8 = 960 in³. Void per carton = 960 − 400 = 560 in³.
  2. Ten cartons: 560 × 10 = 5,600 in³. With 10% allowance: 5,600 × 1.10 = 6,160 in³.
  3. Whole packs = ceil(6,160 ÷ 1,728) = 4.

Compare the displayed result

Expected displayed result: 6,160 in³ fill

FAQs

Should pack volume use compressed shipping volume?

Use verified usable expanded fill volume. Compressed shipping volume does not describe how much cavity the material can fill in use.

Example inputs and options

Starting values are examples unless a field identifies a dated rule. Unit selectors convert only fields marked for conversion. Rates and model options keep the units and basis shown in their labels.

Internal carton length (in)
Example: 12
Internal carton width (in)
Example: 10
Internal carton height (in)
Example: 8
Occupied contents volume (in³)
Example: 400
Identical cartons
Example: 10
Additional allowance (%)
Example: 10
Usable expanded fill volume per pack (in³)
Example: 1728