Understanding paper weights with GSM
In printing and paper, GSM stands for Grams per Square Meter, and it’s a basic measurement to look at when you are choosing papers. GSM shows the weight of the paper, and in practical terms it is used to describe and understand the heaviness of a paper.
The average copy paper in your office’s printers has a GSM around 70 to 80. If you can visualize what that paper feels like, then you can start to imagine some of the differences in other papers.
Tissue paper, for example has a much lower GSM around the 15-30 range. A sheet of the newspaper would be around 50 GSM or so.
At the other end of the spectrum, the average stock used in a folder, book cover, or business card usually has a GSM around 200.
Beyond that things get interesting. We often print business cards on paper stocks with a GSM of 300 or more. This literally adds weight to a printed piece. The affect on a potential client when they are handed a heavy and solid business card can be very memorable adding durability and importance to a design.
GSM also plays a role when deciding how to run a paper on press. It can affect everything from the imposition, to the type of inks, and the drying times. Heavier weights put more strain on certain machines, and each machine has target specifications for paper it can use. Too light a paper and the press destroys the paper, too heavy and the paper destroys the press.
Here is some more information on the differences in GSM and paper types, as well as a few definitions that could be helpful.
It is important to remember that GSM is just one measure of a paper stock. Designers also need to consider the finish, the texture, the brightness, and the opacity of a paper – just to name a few.
GSM can be a good place to start when thinking about and describing the type of paper you want your project to have, but of course you need to feel samples of your potential papers. Any printer worth their inks will have a collection of hundreds maybe even thousands of paper samples to pour through. So take your time, talk with your printer, and find the one paper that will wow your clients.
A few more notes on GSM
GSM describes the weight of the paper as it produced in bulk, not in the cut paper sizes we encounter everyday.
Paper is produced in what are called parent-size sheets, and then they are cut and trimmed to the standard sizes we might see in an office or home environment. These parent-size sheets are quite large, so measuring them by the square meter makes a lot of sense.
For example, a parent-sized sheet of 1 meter-squared (that is roughly 3 and quarter feet squared for those of us a little fuzzy with the metric system) with a gsm of 90 would weigh about 90 grams (roughly a fifth of a U.S. pound), but a single piece of letterhead (8.5″ by 11″) itself would only have a weight of around 5 grams.
One more thing on quality…
On occasion we hear or read people say things like, “The higher the GSM, the higher the quality of paper.” And while from a certain viewpoint this might be true, generally GSM is not a measure of quality. In copy papers, yes, the 60 GSM paper you picked up at the Gas and Sip on the way to the office is more than likely of lower quality than the 80 GSM paper your copier company promotes. But GSM is only a measure of weight, nothing more.
Generalizing quality of paper from one metric is pretty much absurd. Each project is unique to itself, and each paper presents unique qualities for a job. There are some amazing papers in this world with GSMs far lower than that cheap copy paper, but made with top-notch quality and craftsmanship. Again, we say, get out and see as many paper samples as you can!
cutpasteandprint Printing, graphic design, binding, and promotional product specialists in Huntingdon Valley, PA. We proudly serve the Bucks and Montgomery County areas with superior quality, great customer service, and a commitment to getting you and your the best possible printed materials. Our services include: Digital Printing, Offset Printing, Graphic Design, Promotional Items, Bindery, and Copying.
estimating@cutpasteandprint.com • 215.364.3898
