Grams per square metre. The weight of one square metre of that paper. That is the entire definition, and everything people believe about it beyond that is inference.
What each range feels like
| GSM | Where you have held it |
|---|---|
| 70–90 | Office printer paper, a newspaper insert |
| 100–130 | A flyer, a cheap magazine |
| 130–170 | A good magazine page |
| 200–250 | A greetings card, an album page |
| 300 | A postcard, a business card, a cover |
| 350+ | Rigid. Packaging territory |
Ours: 170 GSM magazine inner pages, 250 GSM album inner pages, 300 GSM covers, prints and cards.
What higher GSM actually buys
Three real things, and they are worth knowing individually rather than as “better”.
1. Opacity. A heavier sheet is more opaque, so the photograph on the other side does not ghost through. This is the main reason inner pages are 170 rather than 130 — below about 150 GSM, a dark photograph shows faintly through the page.
2. Stiffness. A page that holds itself when turned, and a cover that does not curl. This is what 300 GSM is for.
3. The feel. Genuine and hard to quantify. Heavier paper reads as more considered before anybody looks at what is printed on it.
What it does not buy
⚠️ Not print quality. The image quality comes from the file and the printing, not the weight of what it lands on. A poor photograph on 300 GSM is a poor photograph on nice paper.
Not longevity, directly. What degrades a print is light, humidity and handling. A heavier sheet survives handling better; it does not resist fading. How long do printed photos actually last →
Not a finish. GSM says nothing about matte or gloss, which is the difference you will actually notice every time you open it. Matte, gloss and satin compared →
Why heavier is not simply better for inner pages
There is a ceiling, and it is not cost.
A 300 GSM inner page does not turn properly. It resists, it does not lie flat in a saddle-stitched book, and forty of them is a brick rather than a magazine.
Inner pages want to be turned; covers want to be rigid. That is why the two numbers are different and why “we use 300 GSM throughout” would be a worse product rather than a better one.
Using it to compare sellers
GSM is the easiest specification to quote, which is exactly why it is quoted most.
Ask about the finish and the binding too. A seller who says “300 GSM” and nothing else has told you one third of what decides how the object feels. How to judge paper quality → · Photo book binding types →
The comparison nobody makes
Sellers quote GSM against each other. The more useful comparison is GSM against what the paper has to do.
- A page that folds through a spine has a ceiling of about 200 GSM.
- A page that does not fold has no ceiling worth caring about.
- A cover has a floor — below about 250 GSM it will not hold its shape.
- A loose print that gets handled wants 300 GSM whatever else is true.
Read that way, our four numbers are not a scale from worse to better. They are four different answers to four different jobs, and a seller using one number everywhere has either one job or has not thought about it.
Frequently asked
What does GSM mean? Grams per square metre — the weight of a square metre of that paper. It is a weight, not a quality score.
Is higher GSM better? For a cover, yes. For inner pages there is a ceiling — above about 200 GSM the pages stop turning properly.
What GSM is good for a photo book? Around 170 for inner pages and 300 for a cover, which is what we use.
Does GSM affect print quality? No. Image quality comes from the file and the printing. GSM affects opacity, stiffness and feel.
Why are your covers and pages different weights? Covers need to be rigid and pages need to turn. One number for both would make a worse object.
Part of our guide to paper and printing. See also: matte, gloss and satin compared and how to judge paper quality.
170 GSM pages, 300 GSM covers: Photo magazines from ₹499 · All 11 keepsakes