GSM ↔ Micron Converter

Why density matters

The same micron thickness has different weight depending on the polymer. PET is denser than BOPP, so 12 μm PET weighs more (higher GSM) than 12 μm BOPP.

• PET ≈ 1.38 g/cm³ → 12 μm ≈ 16.56 GSM
• BOPP ≈ 0.91 g/cm³ → 12 μm ≈ 10.92 GSM
• CPP ≈ 0.90 g/cm³ → 12 μm ≈ 10.80 GSM