Paper weight, expressed in grams per square metre, determines how sturdy and luxurious a book feels. Paper weight sounds technical, but it comes down to one choice: how heavy do you want your paper? Too light and it shows through, too heavy and the book turns unwieldy.
What does grammage mean?
Grammage indicates how much one square metre of the paper weighs. A higher grammage usually means thicker and firmer paper. Watch out: thickness also depends on the paper type — coated (smooth) paper feels thinner at the same weight than bulky paper. Grammage is expressed in grams per square metre; you can read the background to this measure in the explanation of grammage.
Guidelines per application
- 80–100 g/m²: book blocks of novels and text books.
- 115–150 g/m²: books with many illustrations and photo books.
- 170–250 g/m²: luxury photo books and art books.
- 240–300 g/m²: softcover covers.
- Board: hardcover covers (inner core).
Preventing show-through
For a double-sided book block with a lot of imagery you prevent show-through by choosing at least 115 g/m². For pure text 80–90 g/m² is often enough. Unsure about the best weight for your book? Ask for a paper sample or let our specialists advise you.
Paper weight and the feel of your book
The weight of your paper determines how a book feels before anyone even opens it. A novel on 80 gsm feels light and handy; the same novel on 120 gsm feels like a reference work. That is not a matter of better or worse, but of what you want to convey: airy and accessible, or solid and lasting.
Do not forget the practical side either. Heavier paper makes a thick book awkward to hold and noticeably raises your shipping costs, certainly for a print run that has to go out the door. With a photo book you lay on the table that hardly counts; with a book that goes into a bag it counts all the more.
Grammage and the spine width
If you change the paper weight, your spine width changes with it. Going from 90 to 120 gsm on a book of 250 pages quickly makes a difference of several millimetres, and your cover design no longer fits. So decide on your paper before you lay out the cover, not afterwards.
Volume plays a part too: two papers of the same weight can turn out to be different thicknesses. Always recalculate your spine with the paper you actually choose, using the spine width calculator. Still hesitating between two types? Order a single copy first; you only really feel paper once you hold it.
Which weight do you choose for your cover?
For a softcover cover you almost always work between 240 and 300 gsm. Lighter than 240 starts to wave and curls up at the first sign of humidity; heavier than 300 becomes difficult to fold and can crack in the crease when opened. If lamination is applied, the cover gains some firmness, so 250 gsm with matt lamination already feels like a full-fledged cover.
With a hardcover it works differently: there it is not the paper but the board underneath that provides the firmness. The printed sheet glued around it is relatively light, usually around 130 to 150 gsm, because it has to fold tightly around the edges. So you do not feel that weight; what you feel is the board.
Frequently asked questions about paper weight and grammage
What is grammage?
Grammage is the weight of paper in grams per square metre (g/m²). The higher it is, the thicker and firmer the paper usually feels.
Which weight prevents show-through?
At least 90 gsm for double-sided text, and towards 120 gsm if there are photos or coloured areas as well.
Which paper weight do I choose for an ordinary novel?
Around 90 g/m² uncoated. Light enough to keep the book handy, firm enough to limit show-through with double-sided text.
Is heavier paper always better?
No. Heavier paper makes a thick book unwieldy and more expensive to ship, and a novel on 150 gsm reads awkwardly. Choose the weight to suit the use, not the feeling that heavy means expensive.