GSM vs PT: Understanding the Difference
When it comes to packaging, printing, or paper selection, you’ll often come across terms like GSM and PT. Both are important units of measurement that determine the thickness, durability, and overall quality of paper and packaging materials. However, these terms represent different measurement systems. Let’s break down what each means and how they differ.
What is GSM?
GSM stands for Grams per Square Meter. It is a metric measurement used worldwide to define the weight of paper. In simple terms, GSM tells you how much a sheet of paper weighs for a square meter in size.
- Low GSM (35–70 GSM): Lightweight papers such as newspapers or tissue.
- Medium GSM (80–120 GSM): Standard office paper or flyers.
- High GSM (200–400 GSM): Cardstock, premium brochures, and rigid packaging.
In Packaging: Higher GSM means stronger, denser paper. For example, luxury packaging or rigid boxes often use high GSM boards for durability and premium feel.
What is PT?
PT stands for Point and is commonly used in the U.S. to measure thickness of paperboard or packaging material.
- 1 PT = 1/1000 of an inch.
- So, 10 PT equals 0.010 inches in thickness.
In Packaging: PT is especially common when ordering custom boxes, business cards, or cardstock. For instance, a 16 PT business card feels thicker and sturdier than a 12 PT one.
Key Differences: GSM vs PT
| Feature | GSM (Grams per Square Meter) | PT (Point/Thickness) |
| System | Metric (weight-based) | Imperial (thickness-based) |
| Usage | Worldwide, especially Asia & Europe | Mainly U.S. & North America |
| What It Measures | Weight of paper per m² | Thickness of paperboard in thousandths of an inch |
| Example | 300 GSM paper is heavy and strong | 16 PT card is thick and durable |
Conversion Between GSM and PT
There isn’t an exact conversion formula because GSM measures weight while PT measures thickness. Different paper types (coated, uncoated, kraft, etc.) vary in density, meaning a 300 GSM paper won’t always equal the same PT thickness.
However, here’s a rough comparison:
- 10 PT ≈ 250 GSM
- 12 PT ≈ 300 GSM
- 16 PT ≈ 350–400 GSM
Always confirm with your printer or packaging supplier to ensure you’re selecting the right option for your project.
Which Should You Choose: GSM or PT?
- If you’re outside the U.S. (Europe, Asia, etc.): GSM is the standard reference.
- If you’re in the U.S. or Canada: PT is more commonly used.
- For Packaging: Both are important—GSM for strength and PT for thickness feel.
Ultimately, your choice depends on your region, industry standards, and the type of packaging or printing you need.
Final Thoughts
Both GSM and PT are crucial in defining the quality of paper and packaging. GSM gives you an idea of paper weight and durability, while PT tells you about thickness and sturdiness. Understanding these terms helps you communicate better with manufacturers and ensures you choose the right material for your packaging, business cards, or printing needs.
