Paperboard caliper converter
Convert paperboard thickness between points, millimeters and microns.
How it works
In the US, paperboard thickness (caliper) is measured in points: one point is one thousandth of an inch. Elsewhere it's given in microns or millimeters. An 18 pt board is 0.018 in, about 0.46 mm or 457 microns.
Most retail cartons use 14 to 24 pt. Thicker board feels more premium and resists crushing, but it's harder to fold cleanly around small panels and adds to the carton's outside size. Use the folding carton size calculator to see the effect.
Results are estimates based on typical industry values. Confirm final specifications with your supplier or carrier.
Frequently asked questions
What is 18 pt cardboard in mm?
About 0.46 mm.
What does pt mean for paperboard?
Points: thousandths of an inch. 16 pt board is 0.016 inch thick.
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