Box Void Volume Calculator
Check that one rectangular envelope fits in an orthogonal orientation, then subtract its volume. This free volume is not a filler dosage or a protection specification.
Use a saved product specification (optional)
Enter your values
First time using this calculator?
Replace the example values with figures from your supplier sheet or measurements. Choose the unit beside each value. Results update as you type; fix any highlighted field before using the result.
GSM means grams per square metre. Net weight excludes the core and other packaging. MOQ means the minimum order quantity. An optional field can stay blank unless the result you need depends on it.
Prices keep the selected currency; changing its label does not convert an exchange rate. Save or export the result after checking your inputs.
Geometric free volume
Geometric free volume = Internal box volume − Product envelope volume
l = 400; w = 300; h = 200; x = 300; y = 200; z = 150 → Geometric free volume = 15 L; Free-volume share = 62.5 %Saved calculations stay in this browser. No account or cloud backup is created.
Save to a product project (optional)
Choose or create a saved product project ↗This is an illustrative example. Saved or transferred values must be checked against your job.
Calculated from your inputs. Confirm specifications with your supplier.
How sensitive is this result to your assumptions?
Vary one input and inspect geometric free volume
All other entered inputs stay fixed. Ranges are your scenarios, not statistical confidence or supplier performance predictions. This uses the same validated calculator engine.
The formula, made clear.
Check that one rectangular envelope fits in an orthogonal orientation, then subtract its volume. This free volume is not a filler dosage or a protection specification.
How to use this calculator
- 01
Confirm internal box length, internal box width, internal box height, product envelope length, product envelope width, product envelope height.
- 02
Enter consistent units; zero means a confirmed absence of a charge or allowance.
- 03
Review the arithmetic, rounding and limitations before using the result in a purchasing decision.
A calculation you can check
A 24 L internal box minus a 9 L envelope leaves 15 L geometric free space.
- Internal box length
- 400 mm
- Internal box width
- 300 mm
- Internal box height
- 200 mm
- Product envelope length
- 300 mm
- Product envelope width
- 200 mm
- Product envelope height
- 150 mm
l = 400; w = 300; h = 200; x = 300; y = 200; z = 150 → Geometric free volume = 15 L; Free-volume share = 62.5 %Check the displayed formula and units against your quotation. Use measured GSM, net weight and actual layout dimensions where available. Default densities are planning assumptions, not certified material properties. Calculated cost does not certify strength, compatibility or safe loading.
Method, units and material assumptions ↗