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Glossary
Glossary

GSM (paper weight)

Also known as: Grams per square metre · Paper weight

Definition

Grams per square metre — the international measure of paper weight. Higher GSM means heavier, thicker, more substantial paper. Fine-art papers are typically 200gsm and above.

GSM stands for “grams per square metre” — the weight of one square metre of the paper, in grams. It’s the international standard for measuring paper weight and tells you, quickly, whether you’re looking at a flimsy office sheet or a substantial fine-art paper.

To anchor the scale: 70–90gsm is copier and office paper, light and slightly translucent. 120–170gsm is premium copier or matt photo paper, heavier and still flexible. 200–250gsm is entry-level fine-art and photo paper, substantial in the hand. 300–350gsm is proper fine-art weight, stiff and unwilling to curl or dent. 400gsm and above is speciality paper, closer in feel to lightweight board than paper.

For framed prints, paper weight matters for two practical reasons. Heavier paper holds its shape — it doesn’t ripple or warp when humidity changes, and it sits flat against the mount without bowing. And heavier paper feels right when you handle it; collectors who buy a lot of prints develop a tactile sense of when a sheet has the right substance for its size.

GSM doesn’t tell you everything. It doesn’t tell you what the paper is made of (cotton vs wood pulp vs α-cellulose), what its surface is (matt, satin, glossy), or whether it’s acid-free. Two papers at the same GSM can feel quite different — a heavyweight cotton sheet is denser and more opaque than the same weight in coated photo paper.

Our prints are made on Hahnemühle German Etching at 310gsm — heavyweight, α-cellulose, 100% acid-free, with a soft velvety matt surface. It’s the substrate weight you’d find on a museum-quality print, regardless of edition size.

Frequently asked

Common questions about gsm (paper weight)

What GSM is fine-art paper?
Fine-art paper is typically 200gsm and above. Entry-level fine-art and photo papers sit around 200-250gsm; proper museum-quality weights are 300-350gsm. Anything below 200gsm is closer to photo or office paper. Our prints are 310gsm — at the heavier end of the standard fine-art range.
Is higher GSM always better for a print?
Heavier is sturdier (less likely to ripple, warp, or dent), feels more substantial in the hand, and signals quality at a tactile level. But GSM doesn't tell you what the paper is made of, what its surface is, or whether it's acid-free — a heavy wood-pulp paper still yellows over time. Archival fibre matters more than weight alone.
How does GSM compare to the US lb system?
GSM (grams per square metre) is the international standard and is independent of paper format. The US "lb" system is based on the weight of 500 sheets at a paper's basic size, which varies by paper type — so a 100lb cover and a 100lb text weigh different amounts per square metre. GSM is the more useful comparison: every paper at the same GSM is dimensionally comparable.
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