What Does GSM Mean in PVC Leather and Coated Fabric?
Why GSM matters
Two rolls can look the same and both be called "1 mm rexine", yet one may contain much more PVC than the other. GSM shows how much material you are actually buying. It is one of the most useful numbers for comparing quotes and for checking that repeat orders match the approved sample.
How to measure GSM yourself
- Cut a square exactly 10 cm × 10 cm (an area of 100 cm², which is 0.01 m²). A metal ruler and a sharp cutter or a GSM round cutter give the most accurate result.
- Weigh it on a scale that reads to at least 0.01 g.
- Multiply the weight in grams by 100. That is the GSM.
Example: a 10 × 10 cm sample weighing 6.2 g has a GSM of 6.2 × 100 = 620 GSM. Measure three or four samples from different parts of the roll and average them.
From GSM to weight per running metre
Rexine is usually sold per metre, so it helps to know how much one running metre weighs. Multiply GSM by the width in metres:
| GSM | Width | Weight per running metre |
|---|---|---|
| 500 | 54 in (1.37 m) | 500 × 1.37 = 685 g |
| 620 | 54 in (1.37 m) | 620 × 1.37 ≈ 849 g |
| 800 | 54 in (1.37 m) | 800 × 1.37 = 1,096 g |
If one supplier quotes per kg and another per metre, this calculation lets you compare them fairly.
GSM vs thickness
Thickness and GSM are related but not the same. A brushed or foamed layer can add thickness without adding much weight, while a dense compact layer adds weight without much thickness. Ask for both numbers, and check both on delivery.
GSM for coated fabrics
For PVC coated fabrics used in covers, tents and tarpaulins, GSM is usually the headline specification, together with the base fabric type and coating on one or both sides. Heavier GSM generally means more PVC and better waterproofing and durability, at a higher cost. See single vs double side coated fabric.
Quick FAQ
How do I calculate GSM?
Weigh a 10 cm × 10 cm sample in grams and multiply by 100.
Is higher GSM always better?
Not always. Higher GSM usually means more material and durability but also more weight and cost. Choose the GSM that suits the application.