Paperboard GSM to pt converter
Convert paperboard caliper between points (pt), GSM (g/m²), millimeters (mm) and microns for folding cartons, kraft and rigid boxes.
GSM-to-caliper varies slightly by mill press density (±5–8%). Tell your account manager what goes inside the box and we recommend the right board weight.
Questions
What does "pt" (points) mean in custom boxes?
One point equals 1/1000 of an inch (0.001 in or 0.0254 mm). An 18 pt folding carton board is 0.018 inches (0.46 mm) thick—the everyday standard for retail cosmetic, supplement, and food cartons.
Why isn’t GSM-to-pt identical across every paperboard?
Points measure thickness (caliper), while GSM measures weight per square meter. Dense coated SBS board weighs slightly more per point than bulkier uncoated kraft or greyboard.
Still have a question? Ask a packaging specialist.
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Standard Paperboard & Rigid Greyboard Caliper Reference Chart
| US Caliper (pt) | Metric (mm / µm) | Approx. SBS GSM | Common Custom Packaging Uses |
|---|---|---|---|
| 12 pt | 0.30 mm / 305 µm | ~250 GSM | Light belly bands, insert cards, hang tags |
| 14 pt | 0.36 mm / 356 µm | ~270 GSM | Lip balm, mascara, small cosmetic & tuck cartons |
| 16 pt | 0.41 mm / 406 µm | ~300 GSM | Everyday retail folding cartons, soap & supplement boxes |
| 18 pt | 0.46 mm / 457 µm | ~325–350 GSM | Serum bottles, tinctures, bakery & food cartons |
| 24 pt | 0.61 mm / 610 µm | ~420–450 GSM | Heavy candle cartons, beverage carriers, display boxes |
| 60–80 pt rigid | 1.5–2.0 mm | 1,000–1,200 GSM core | Magnetic closure, two-piece & drawer luxury rigid boxes |
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<iframe src="https://cubitpack.com/tools/paperboard-thickness-converter" width="100%" height="620" style="border:1px solid #e2e4ea;border-radius:12px;background:#fff;" loading="lazy" title="CubitPack Free Paperboard GSM to pt converter"></iframe>
<p style="font-size:12px;color:#555;margin-top:6px;">Free tool by <a href="https://cubitpack.com/tools/paperboard-thickness-converter">CubitPack Paperboard GSM to pt converter</a> · <a href="https://cubitpack.com/boxes">Custom Boxes</a></p>Popular custom packaging sized with this tool
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