Materials
Caliper
Caliper is the measured thickness of a sheet material, commonly expressed in millimetres or micrometres.
What it means in packaging
Board thickness influences panel offsets, folds and assembled fit. It is different from grammage: two papers with the same mass per square metre can have different thicknesses because their composition and density differ.
A practical example
Switching to thicker board can tighten a tuck closure even when the requested inside box dimensions stay the same.
What to check
Use the supplier’s stock specification or a measured sample. Do not derive caliper from gsm alone.