What Does GSM Mean? Paper Weight Explained

What Does GSM Actually Stand For?

GSM stands for "grams per square metre." It is the standard measurement for paper weight used across the printing industry. A sheet of 100gsm paper weighs exactly 100 grams per square metre, regardless of the sheet size. A sheet of 300gsm card weighs 300 grams per square metre.

The higher the GSM number, the heavier the paper. Heavier paper generally feels thicker and more rigid, though this is not always a perfect correlation (more on that below).

Weight vs Thickness: They Are Not the Same

This trips people up regularly. Two sheets of paper can both be 300gsm but feel different in your hand. That is because GSM measures weight, not thickness. A coated (glossy) 300gsm sheet is often thinner than an uncoated 300gsm sheet because the coating compresses the fibres.

Thickness is measured separately in microns. For most print orders, GSM is the number you need to care about. It tells you roughly how the paper will feel, how stiff it will be, and what it is suitable for.

Common Paper Weights and What They Are Used For

80gsm to 100gsm: Everyday Paper

This is standard copier and office paper. The sheets you load into your home or office printer are typically 80gsm. At this weight, paper is light, flexible, and easy to fold. It is fine for internal documents and drafts but too thin for anything you would hand to a customer.

120gsm to 170gsm: Leaflets and Inserts

This range covers most flyers and leaflets. At 130gsm, you get a sheet that feels noticeably sturdier than copier paper but still folds easily. 150gsm is a popular choice for tri-fold leaflets and brochure pages. 170gsm sits at the top of this range and has a premium feel for a single-sheet handout without being stiff.

200gsm to 250gsm: Heavyweight Flyers and Covers

Once you get above 200gsm, paper starts to feel like light card. A 250gsm flyer will not flop when you hold it by one edge. This weight range works well for premium flyers, presentation folders, and brochure covers. Many of our customers in Belfast choose 250gsm for flyers they want to stand out from the usual 130gsm leaflets.

300gsm to 350gsm: Standard Card

This is the sweet spot for most card-based products. Business cards are typically printed on 350gsm or 400gsm card. Postcards, loyalty cards, and table talkers work well at 300gsm to 350gsm. At this weight, the material is rigid and does not bend easily. It feels professional in the hand.

400gsm to 450gsm: Premium Card

The thickest stocks commonly available for commercial printing. 400gsm is the go-to weight for premium business cards that make an immediate impression. 450gsm feels almost board-like and is used for things like swing tags, high-end postcards, and packaging elements. If you pick up a business card and think "that feels expensive," it is probably 400gsm or above.

How Paper Weight Affects Perception

People judge the quality of your business by the materials you hand them. Research consistently shows that heavier paper is associated with higher quality, greater trustworthiness, and better perceived value. A business card on thin card feels cheap, regardless of how good the design is.

This does not mean you should always pick the heaviest option. A 450gsm flyer for a takeaway menu would be overkill (and expensive). The right weight depends on the product, the audience, and how it will be used. For more on choosing paper types, read our guide on choosing the right paper stock.

Coated vs Uncoated: How Finish Affects Feel

The GSM number only tells you part of the story. The finish matters too. A 350gsm silk-coated card has a smooth, slightly shiny surface. The same weight in an uncoated stock feels rougher and more textured. Neither is better or worse; they just suit different purposes.

• Gloss coated: Shiny, vivid colours, photographs look sharp. Fingerprints show easily.
• Silk/satin coated: Smooth but not shiny, easy to read, good colour reproduction. The most popular finish for business cards and flyers.
• Uncoated: Natural feel, slightly rough texture, best for a classic or eco look. Ink sits on the surface differently, so colours appear slightly softer.
• Recycled: Usually uncoated with a distinctive texture. Weights are available from around 100gsm up to 350gsm.

Quick Reference Guide

• Flyers and leaflets: 130gsm to 170gsm (silk or gloss)
• Premium flyers: 250gsm to 300gsm (silk)
• Brochure inner pages: 130gsm to 170gsm (silk)
• Brochure covers: 250gsm to 350gsm (silk or gloss)
• Business cards: 350gsm to 450gsm (silk, with optional lamination)
• Postcards: 300gsm to 400gsm (silk or gloss)
• Posters: 170gsm to 250gsm (silk or gloss)
• Letterheads: 100gsm to 120gsm (uncoated)

Choosing the Right Weight for Your Job

If you are ordering for the first time and not sure which weight to pick, here is a simple approach. Think about how the printed piece will be used. Will it be posted through a letterbox? Lighter paper (130gsm to 170gsm) keeps postage costs down. Will it sit on a counter for people to pick up? Something at 250gsm or above will hold its shape. Will someone carry it in their wallet? Go for 350gsm or thicker so it survives.

When you order from us, each product page lists the available paper weights. If you are still unsure, drop us a message. We are happy to post you a sample pack so you can feel the different weights before committing to a full order.