Math
Rectangular prism
Find the volume and closed surface area of a rectangular box.
Calculators / Shipping & logistics / Carton space diagonal
Carton space diagonal calculator
Find the corner-to-corner distance through an ideal rectangular carton.
On this page
Space diagonal53.85cm
Base diagonal50cm
Calculator controls
How to calculate
Find the corner-to-corner distance through an ideal rectangular carton.
Space diagonal =
sqrt(length^2+width^2+height^2) cmBase diagonal =
sqrt(length^2+width^2) cmWorked example
- Internal length (cm): 40
- Internal width (cm): 30
- Internal height (cm): 20
- Space diagonal: 53.85 cm
- Base diagonal: 50 cm
Assumptions and limits
Use internal dimensions. A diagonal alone does not prove that a rigid item can enter, rotate or fit with its width, padding and opening constraints.
Results are rounded for display; calculations use unrounded values. Read our calculation methodology.
Understanding the result
Find the corner-to-corner distance through an ideal rectangular carton. First find the base diagonal, then combine that distance with height using the Pythagorean theorem.
When this tool is useful
First find the base diagonal, then combine that distance with height using the Pythagorean theorem.
Understanding your inputs
| Input | Example |
|---|---|
Internal length (cm) length | 40 |
Internal width (cm) width | 30 |
Internal height (cm) height | 20 |
Frequently asked questions
What assumptions should I check?
Use internal dimensions. A diagonal alone does not prove that a rigid item can enter, rotate or fit with its width, padding and opening constraints.
How can I check the result?
Start with the labelled example. Keep units consistent, calculate without intermediate rounding and change one input at a time. The diagram explains the model; the result table supplies the numerical answer.