Paper Thickness Conversion Chart
Understanding Paper Thickness in Packaging
When it comes to packaging, “thickness” can mean a dozen different things depending on who you ask. One person says 100 GSM, another says 3 mil, and a third swears by 75 µm. They might all be talking about the same thing—just in different units.
That’s why this paper thickness conversion chart exists: to make life easier for buyers, designers, and production teams who deal with paper, film, or laminates every day. Whether you’re comparing kraft linerboard, art paper, or coated stock for your pouches, this guide translates GSM into real-world thickness you can feel.
What GSM Really Means
GSM (grams per square meter) measures the weight of paper, not its actual thickness. Still, heavier papers usually end up thicker, so printers and converters often use GSM as a shorthand for rigidity or strength.
In flexible packaging, GSM affects:
- Durability: Heavier papers resist tearing and creasing.
- Print quality: Thicker stock allows richer ink coverage.
- Fold & feel: Critical for retail display and perceived quality.
Paper Thickness Conversion Chart (Approximate)
| Paper Type | GSM | Millimeters (mm) | Microns (µm) | Mils |
|---|---|---|---|---|
| Kraft Paper | 40 gsm | 0.06 mm | 60 µm | 2.4 mil |
| 60 gsm | 0.09 mm | 90 µm | 3.5 mil | |
| 80 gsm | 0.12 mm | 120 µm | 4.7 mil | |
| 100 gsm | 0.14 mm | 140 µm | 5.5 mil | |
| 120 gsm | 0.17 mm | 170 µm | 6.7 mil | |
| C2S Art Paper | 80 gsm | 0.07 mm | 70 µm | 2.8 mil |
| 100 gsm | 0.09 mm | 90 µm | 3.5 mil | |
| 128 gsm | 0.12 mm | 120 µm | 4.7 mil | |
| 157 gsm | 0.15 mm | 150 µm | 5.9 mil | |
| Matte Coated Paper | 80 gsm | 0.08 mm | 80 µm | 3.1 mil |
| 100 gsm | 0.10 mm | 100 µm | 3.9 mil | |
| 128 gsm | 0.13 mm | 130 µm | 5.1 mil | |
| 157 gsm | 0.16 mm | 160 µm | 6.3 mil | |
| Wood-Free Offset Paper | 70 gsm | 0.09 mm | 90 µm | 3.5 mil |
| 80 gsm | 0.10 mm | 100 µm | 3.9 mil | |
| 100 gsm | 0.13 mm | 130 µm | 5.1 mil | |
| 120 gsm | 0.15 mm | 150 µm | 5.9 mil |
Note: Values vary slightly by fiber type, moisture, and finishing. Use this as a reference, not a certification chart.
Why Paper Thickness Matters in Packaging
When selecting paper for flexible packaging:
- Kraft liners (80–150 gsm): Strong and recyclable.
- C2S or matte coated stock: Offers print gloss and visual polish.
- Wood-free papers: Ideal for inner layers and labeling.
Heavier isn’t always better—choose based on the product, barrier needs, and machine speed.
Common Conversions in Flexible Packaging
If you’re switching between paper and film lamination, here’s how the numbers translate:
| Unit | Equivalent |
|---|---|
| 1 mil | 25.4 µm |
| 1 µm | 0.001 mm |
| 1 mm | 39.37 mil |
| 1 gsm (approx. paper) | 1.5 – 2.0 µm thickness range |
Choosing the Right Paper Weight
When selecting paper for flexible packaging:
- Kraft liners (80–150 gsm): Strong and recyclable.
- C2S or matte coated stock: Offers print gloss and visual polish.
- Wood-free papers: Ideal for inner layers and labeling.
Heavier isn’t always better—choose based on the product, barrier needs, and machine speed.
Converting Paper Thickness into Real-World Results
Understanding paper thickness is more than numbers on a chart—it’s how your packaging performs, feels, and protects what’s inside. Whether you’re working with kraft, coated stock, or laminates, knowing the right GSM or micron range keeps your project efficient and on-brand.
Hawk Flex Packaging helps brands take the guesswork out of material selection. From pouch liners to specialty wraps, we match specs that look sharp, run clean, and deliver consistent quality. For help selecting the right paper or laminate, contact our team for quick guidance and a quote.
Raine is the visionary behind Hawk Packaging, having founded the company in 2012 with a mission to revolutionize the packaging industry. With a blend of entrepreneurial spirit and innovative thinking, Raine built Hawk Packaging from the ground up, establishing it as a leader in the field. Today, Raine continues to play a pivotal role as an advisor, offering his wealth of knowledge and strategic guidance to ensure the company’s ongoing success. Raine’s passion and dedication remain at the heart of Hawk Packaging.