Translate carton dimensions
Carton internal and external dimensions calculator
Carton listings do not always use the same measurement convention. Convert between approximate inside and outside dimensions using the stated board thickness.
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✓ Planning result
Change any value and calculate again for a new result.
01 / Method
How to use this tool
- 1
Select the direction of conversion.
- 2
Enter all three carton dimensions in the same unit.
- 3
Use the measured or supplier-stated combined board thickness.
02 / Model
Assumptions
- A simple two-caliper adjustment is used on every axis.
- Board thickness is uniform and the carton is square.
03 / Boundaries
Limitations
- Real score-to-score dimensions and flap construction vary by carton style.
- Compression and moisture can change finished size.
04 / Common questions
Frequently asked questions
Why add or subtract twice the board thickness?
Each dimension crosses two opposing carton walls.
Can I use nominal flute thickness?
Yes for early estimates, but measured combined-board caliper is better for purchasing decisions.