McKee formula
An equation from McKee, Gander and Wachuta (1963) that estimates box compression strength from edge crush, caliper and perimeter.
In practice
The simplified form Packgent uses is BCT ≈ 5.87 × ECT × √(caliper × perimeter). It fits regular slotted boxes best and is an estimate, not a test result.
Related terms
- Box compression test (BCT)
- The top-to-bottom load an empty box carries before it fails, measured between two platens in a compression tester.
- Edge crush test (ECT)
- The load per inch of edge that a short column of board carries standing on its edge, flutes vertical.
- Caliper
- The thickness of a sheet of board, usually given in inches or millimetres.
Definitions written by Packgent, last reviewed 2026-10-27. All terms.