GSM to Mil Calculator

Convert GSM (grams per square meter) to Mil thickness by accounting for material density. Get accurate thickness measurements for paper, plastic, fabric, and more.

Select Material & GSM Get Thickness Result

Material & GSM Input

Paper

0.7-1.0 g/cm³

Plastic Film

0.9-1.4 g/cm³

Fabric

0.3-0.8 g/cm³

Metal Foil

2.7-8.9 g/cm³

Grams per square meter (1-5000)

Thickness Result

Select a material and enter GSM value to see thickness conversion

GSM and Mil

GSM (grams per square meter) measures the weight of paper or fabric, but thickness depends on material density. The same GSM value can produce very different thicknesses depending on whether it's paper, plastic, fabric, or metal.

This calculator accounts for density to provide accurate thickness conversions. A material with lower density will be thicker at the same GSM, while higher density materials will be thinner.

Understanding this relationship is crucial for printing, packaging, textiles, and manufacturing industries where precise thickness specifications matter.

GSM to Mil Conversion Formula

Step 1: Calculate Thickness in Millimeters

Thickness (mm) = GSM ÷ Density

Step 2: Convert to Mil (Thousandths of an Inch)

Thickness (mil) = Thickness (mm) × 39.37

Density is measured in grams per cubic centimeter (g/cm³) and varies significantly by material type.

Example: 120 GSM paper with density 0.8 g/cm³

Thickness (mm) = 120 ÷ 0.8 = 0.15 mm

Thickness (mil) = 0.15 × 39.37 ≈ 5.9 mil

Material Density Reference

Common Material Densities

Material Type Density Range (g/cm³) Typical GSM Range Example Thickness
Newsprint Paper 0.6 - 0.7 45 - 55 ~3.0 - 4.5 mil
Office Paper 0.7 - 0.8 70 - 100 ~4.0 - 6.0 mil
Cardstock 0.8 - 1.0 200 - 300 ~7.5 - 15 mil
Plastic Film (PET) 1.3 - 1.4 8 - 50 ~0.2 - 1.5 mil
Cotton Fabric 0.3 - 0.5 100 - 400 ~7.5 - 60 mil
Aluminum Foil 2.7 50 - 200 ~0.7 - 2.8 mil

Density values can vary by manufacturer and specific material composition.

GSM to Mil Conversion Examples

Practical Thickness Comparisons

120 GSM Materials

Paper (0.8 g/cm³): 5.9 mil
Plastic (1.3 g/cm³): 3.6 mil
Fabric (0.4 g/cm³): 11.8 mil
Aluminum (2.7 g/cm³): 1.7 mil

200 GSM Materials

Paper (0.8 g/cm³): 9.8 mil
Plastic (1.3 g/cm³): 6.1 mil
Cardstock (1.0 g/cm³): 7.8 mil
Fabric (0.4 g/cm³): 19.7 mil

Same GSM, different densities = different thicknesses. Always consider material type for accurate measurements.