GSM means grams per square metre. A higher GSM usually means a heavier sheet, but it does not automatically mean the paper is thicker, stiffer or better. The best choice depends on the product, finish, handling and printing method.
Paper weight affects how a printed piece feels, folds, mails, stands up to handling and supports colour. It also influences cost. Choosing the heaviest available stock is rarely the goal; the right stock should feel appropriate for the job and perform reliably through printing and finishing.
What does GSM mean?
GSM is short for grams per square metre. It describes grammage: the mass of one square metre of paper. For example, one square metre of 150gsm paper weighs 150 grams. Because GSM is based on a fixed area, it is easier to compare than the American pound-weight system, where the number can refer to different sheet sizes and paper categories.
GSM tells you how much fibre or material is present by area. It does not describe the complete construction of the sheet. Coating, fibre type, compression, surface finish and manufacturing process all influence how the paper feels and performs.
Common paper weights at a glance
| Typical range | Common uses | General feel | Points to consider |
|---|---|---|---|
| 80–100gsm | Letterheads, office documents, forms and internal stationery | Light and flexible | Easy to write on; show-through can matter with heavy two-sided coverage |
| 115–150gsm | Flyers, leaflets, menus, lightweight posters and booklet text pages | More substantial than office paper | Good for economical marketing pieces and distribution |
| 170–200gsm | Premium flyers, brochure covers, short-run menus and presentation sheets | Noticeably firmer | Folding method and grain direction become more important |
| 250–300gsm | Postcards, invitations, booklet covers, presentation folders and light cards | Card-like | Scoring may be needed before folding to reduce cracking |
| 350–400gsm | Business cards, premium postcards and sturdy covers | Heavy and rigid | Not suitable for every printer or every folding style |
These ranges are practical starting points, not fixed rules. Availability varies by paper brand, coating, colour and product. A finished piece can also include lamination, folds, binding or multiple panels that change how substantial it feels.
Why two papers with the same GSM can feel different
Two 300gsm papers can have noticeably different thickness and stiffness. A smooth coated sheet may be compressed more tightly than a bulky uncoated stock. Both can weigh the same per square metre while one feels thicker, softer or more rigid.
Often called caliper. It is the physical depth of the sheet and is measured separately from GSM.
Affected by fibre structure, grain direction, coating and thickness — not weight alone.
Gloss, silk, matt and uncoated papers reflect light and reproduce colour differently.
When presentation matters, compare an actual sample rather than relying only on the GSM number. A sample helps you judge colour, texture, opacity, stiffness and how the stock works with your artwork.
How to choose paper weight for each product
Business cards
Business cards usually benefit from a firm stock that resists bending in a wallet or card holder. Around 350–400gsm is common, but coating, lamination, texture and special finishes can matter as much as the base weight. Explore our business card printing options →
Flyers and leaflets
A handout should be easy to distribute while still feeling intentional. Lighter stocks keep larger quantities economical; heavier stocks feel more premium and hold their shape better. The correct choice depends on whether the flyer is handed out once, displayed on a counter or kept for reference. View A5 flyer printing →
Brochures and booklets
Text pages are normally lighter than covers so a booklet opens and turns comfortably. The page count, binding method and grain direction influence how heavy the finished booklet becomes. A thick text stock can make a high-page-count booklet bulky and harder to bind cleanly. Explore booklet and magazine printing →
Letterheads
Letterhead needs to feel professional while feeding reliably through office printers. An uncoated 90–120gsm stock is often practical because it accepts handwriting and overprinting, but compatibility should be confirmed with the printer that will be used. View custom letterheads →
Posters and display prints
Posters are selected for the display method as well as the paper feel. A framed poster, a short-term wall poster and an outdoor display may require different stocks or entirely different materials. For outdoor or longer-term displays, paper may not be the correct substrate. Explore poster printing →
Paper weight, folding and finishing
As paper becomes heavier or more heavily coated, folding without preparation can produce a raised edge or cracking along the fold. Scoring creates a controlled line before folding and is often recommended for heavier stocks, especially where solid ink crosses the fold.
Grain direction also matters. Paper usually folds more cleanly with the grain than across it. For brochures, folders and booklet covers, the finished size and fold direction should be planned before the stock is confirmed.
- Check opacity for two-sided printing. Lighter papers can allow dark images or text from the reverse side to show through.
- Choose a surface that suits the artwork. Coated stocks sharpen photographs and saturated colour; uncoated stocks provide a more natural feel and are usually easier to write on.
- Plan folds and binding early. Stock weight affects scoring, saddle stitching, perfect binding and how the finished piece opens.
- Consider distribution. Mailing weight, packing space and handout quantities can make an unnecessarily heavy stock expensive.
- Ask for a sample when feel matters. GSM alone cannot show texture, stiffness, shade or coating.
Not sure which paper to specify?
Send us the product, finished size, quantity, page count, printing sides and desired finish. Our Auckland team can recommend a practical stock and arrange delivery throughout New Zealand.
Common paper weight questions
Is higher GSM always better?
No. Higher GSM means more mass per square metre, not automatically better quality. A lighter stock may be the correct choice for letterheads, booklet pages, mailers or high-volume handouts.
Does higher GSM mean thicker paper?
Usually, but not always. Paper density, coating and manufacturing affect thickness. Two stocks with the same GSM can have different caliper and stiffness.
What GSM should I use for business cards?
Many business cards use stock around 350–400gsm, but the best result also depends on coating, lamination, texture and finishing. Compare samples when the feel is important.
What is the difference between GSM and lb?
GSM uses the weight of one square metre and is consistent across paper types. The lb system is based on the weight of a ream at a category-specific basis size, so the same lb number can mean different actual weights for different paper grades.
Can heavy paper be folded?
Yes, but scoring may be needed before folding. Grain direction, coating and ink coverage across the fold also affect the result.
Technical reference
GSM is the common expression of paper grammage. The formal determination method is described in ISO 536:2019 — Paper and board: Determination of grammage. Product suitability still depends on the exact paper specification and finishing process.