When it comes to printing, paper is so much more than you might think. From the glossy pages of a magazine to the sturdy cover of a paperback book, every printed piece starts with a choice. You may be wondering, “which paper thickness should I choose?”
Understanding paper thickness is a must for producing a final product that looks, feels, and performs exactly as you envision it. Whether you’re printing business cards, brochures, posters, or books, the right paper can affect everything from making a powerful first impression to maintaining a book’s durability for decades to come.
In this guide, we’ll help you better understand paper thickness for printing, what the different measurements mean, and how to choose the right paper for your project. Here’s what you need to know:
Why does paper thickness matter?
Paper thickness is about more than just how your printed piece feels in your hands. It plays a vital role in overall durability, as thicker paper is more resistant to tears and being bent over time. Heavier papers also feel more premium, which adds to their professionalism and care.
Depending on the type of product, you’ll also want a firmer design or something more flexible. For example, postcards or packaging inserts have to be stiff to maintain durability. Others, like book pages or flyers, are more flexible. Keep in mind, too, that not all printers handle all different types of paper thicknesses equally. The wrong paper weight may cause paper jams or poor ink absorption.
How is paper thickness measured?
Depending on where you’re located in the world, paper thickness is measured in one of three ways. The most common and widely used system of measurement (particularly outside the U.S.) is GSM. This is how much a square meter of the paper weighs in grams. The higher GSM, the thicker and heavier the paper. For reference:
- 35–55 GSM - Newsprint
- 70–90 GSM - Typical office copy paper
- 100–120 GSM - Letterheads, flyers
- 130–170 GSM - Posters, magazine pages
- 200–300 GSM - Premium flyers, brochures
- 300–400+ GSM - Business cards, postcards
The biggest benefit of using GSM is that it’s precise and universally consistent. The drawback, though, is that it doesn't tell you much about the actual thickness of the paper in millimeters or inches.
In the U.S., paper thickness is often measured in points (pt), or mils, where one point is 1/1000th of an inch. So, 10 pt paper is 0.010 inches thick and 16 pt paper is 0.016 inches thick. This unit of measurement is often used in commercial printing, particularly for postcards, covers, and packaging. It directly measures the thickness in understandable, tangible units, but it doesn’t always match weight (GSM) since the density of the paper can be different.
The last method is basis weight, and this method is still common in the U.S. Basis weight refers to the weight of a 500-sheet ream of paper, but the size of those sheets depends on the paper type. So, a 20 lb bond paper would not equal a 20 lb cover paper. As you might imagine, this method gets confusing fast, so GSM is usually used for clarity and convenience.
Types of paper by thickness
When you see the different paper types in context, it makes much more sense and helps you move forward with choosing the right paper thickness for printing. Here are some standard thicknesses:
- Lightweight paper - 35-90 GSM - Often used for newspapers, mass printing, and manuals. It’s economical and lightweight, but not very durable.
- Medium-weight paper - 100-170 GSM - Used for flyers, letterheads, and internal brochures. This is a good balance between quality and cost. Not recommended for high-end applications.
- Heavyweight paper - 200-300 GSM - Typically used for brochures, postcards, and invitations. These paper products have a more professional look and durable feel, but are harder to fold without scoring them.
- Extra-heavy cardstock - 300-400 GSM - Used on business cards, packaging inserts, and covers. Cardstock has a premium feel, but may not be compatible or suitable for all printers.
Does coated vs. uncoated paper affect thickness?
The answer is both yes and no. Coating affects the surface feel and ink absorption, but it only slightly affects the actual physical thickness. It can, however, change how the paper feels to the touch. Coated paper has a glossy or matte finish that sits on the top, which makes colors pop and text look crisp. It’s best for photos, booklets, and brochures. Uncoated paper is more absorbent and textured. It’s best for vintage-style aesthetics or for writing or sketching.
For books, it’s best to choose anywhere from 70-100 GSM (4-6 pt) for the interior pages, while the cover should be anywhere from 200-300 GSM (10-14 pt). Softer interior pages and a durable, protective cover give you the best of both worlds.
Choosing the right paper thickness
Choosing the right paper thickness is about more than just numbers — it’s about creating the kind of impression you want your readers to have. It’s also about understanding how your material will be used and the level of quality that your brand represents. Whether you’re printing a book cover or a stack of sharp business cards to help boost your author profile, knowing how GSM, points, and finishes all work together can help you decide on paper thickness with greater confidence.
It all boils down to understanding what your goal is and how paper thickness can help you reach it. Still need help making sense of it all? The experts at OnPress Book Printing are here to help. As specialists in printing all types of materials, incluing paperback books and hardback books, our expertise and commitment to quality are second to none.
Contact us today to learn more about our book printing services and how we can help you print anywhere from a few copies all the way to thousands.