What is Paper GSM? A Complete Guide to Paper Weight & Thickness

It is a common misconception that paper GSM and paper thickness are identical. While they are correlated, they are not the same. Thickness is measured in microns ($\mu m$) or points (pt), which refers to the caliper (distance between surfaces) of the sheet.

Two different papers can have the same paper GSM but different thicknesses due to the fiber density or coating. For example, a porous, uncoated kraft paper might be thicker than a dense, glossy coated art paper, even if they weigh exactly the same.

Here is a general reference guide for packaging materials:

• 80–100 GSM: Standard office paper. Too thin for packaging, used for text documents.
• 120–150 GSM: Used for flyers or internal box liners.
• 250–300 GSM: Cardstock. Ideal for folding cartons and cereal boxes.
• 350–450 GSM: Heavy duty cardstock. Used for premium rigid boxes or luxury retail packaging.

Selecting the correct paper GSM is a balancing act between protection and presentation. If you choose a material that is too light, your box may collapse during stacking or shipping. If you choose a material that is excessively heavy, you increase your production costs and shipping fees without adding necessary value.

For most e-commerce applications, corrugated mailer boxes are the standard. These utilize a combination of liners. A typical corrugated board might use a 120 GSM inner liner, a fluted middle layer, and a 140 GSM outer test liner. However, for luxury retail packaging where the “unboxing experience” is paramount, we recommend starting with at least 350 GSM to provide a premium, substantial feel in the customer’s hand.

If you are unsure which weight suits your product, you can request a sample kit. At Gangda, we offer a variety of material options in our Custom Mailer Boxes to help you feel the difference before you commit to a full production run.

💡 Gangda Insider Tip:

Don’t assume that a higher paper GSM is always superior for print quality. Heavier, highly textured papers can sometimes absorb ink unevenly. If your design features intricate, high-resolution graphics, a slightly lower GSM with a smooth, coated finish often yields sharper results than a heavier, rougher stock.

Mastering the concept of paper GSM empowers you to make smarter decisions for your supply chain. It allows you to communicate clearly with manufacturers, ensuring you receive packaging that looks professional and performs reliably. By matching the right weight to your product’s needs, you optimize both protection and budget.

Ready to start your packaging project? Contact our team today to discuss the ideal material specifications for your brand.