Skip to content In the packaging and printing industry, various types of papers are available, including text stock, coated stock (also known as cover stock), and uncoated stock. We will review the conversion process for each material. But at first, let’s take a look at the types of papers.
Use this calculator to convert PT units and lbs units to GSM.
Please note: This calculator will only calculate uncoated paper stock to GSM unit. For converting coated stock, you can read the blog below. Thanks.
Text stock is a type of paper used in printing pages of books, magazines, brochures, and other printed materials. It’s a material where a large amount of text is present. It’s a lighter and thinner material compared to other stock options available in the market, and perfect for printing text.
Uncoated stock, also known as cardboard stock, is a thicker material compared to text stock. Perfect printing and packaging design. This material is highly durable and customizable, making it ideal for manufacturing custom boxes.
Coated stock is available in two variations: C1S and C2S. It’s a coated cardboard that comes with added protection of lamination. You can also use this material for printing and customizing packaging boxes.
Below we have provided a table of conversion of text stock PT to GSM:
Text Stock in PT | Text Stock in GSM |
10pt | ~60 GSM |
12pt | ~72 GSM |
14pt | ~84 GSM |
16pt | ~96 GSM |
18pt | ~108 GSM |
Here’s how you can convert Text PT stock to GSM
Below, we have provided a conversion table of Uncoated Stock PT to GSM:
Uncoated Stock in PT | Uncoated Stock in GSM |
10pt | ~140 GSM |
12pt | ~168 GSM |
14pt | ~196 GSM |
16pt | ~224 GSM |
18pt | ~252 GSM |
Here’s how you can calculate the conversion:
As we have discussed above, coated stock comes in two different variations, which we will cover below. Let’s start C1S.
C1S cardboard is available in three different coating variations: low coating, medium coating, and high coating.
The low coating adds approximately 50 coating weight adjustments in the conversion factor, which is 1400 in this case. For medium, it is 100, and for high coating, 150. The coating weight adjustment.
For the conversion table, we are using a medium coating adjustment:
C1S Covered Stock in PT | C1S Covered in GSM |
10pt | ~150 GSM |
12pt | ~180 GSM |
14pt | ~210 GSM |
16pt | ~240 GSM |
18pt | ~270 GSM |
Here is the formula for calculating C1S Stock PT into GSM:
Just like C1S, C2S also features a coated surface on both sides, which helps make the material sturdy and thick.
Here’s how you can calculate GSM from C2S pt:
Please note that this will have two C values, such as C₁ (coating weight on side 1) and C₂ (coating weight on side 2).
In our case, we have C2S that is coated on one side with medium adjustment and on the other side with high adjustment, for the 8pt cardboard.
C2S Coated Stock (PT) | C2S Coated Stock (GSM) |
10pt | ~165 GSM |
12pt | ~198 GSM |
14pt | ~231 GSM |
16pt | ~264 GSM |
18pt | ~297 GSM |
20pt | ~330 GSM |
22pt | ~363 GSM |
24pt | ~396 GSM |
Now you know how you can convert if you have stock in PT and want the result in GSM for manufacturing purposes. If you are still confused, you can read our detailed guide on PT vs GSM.
There is one more measurement that is often used in packaging and printing companies, which is LBs, meaning Pounds. We have taken the liberty to also providing the information on that too.
Converting lbs to GSM isn’t as complicated as PT. Here’s how you can convert your text stock and covered stock from lbs to GSM:
For text stock: GSM ≈ lbs X 1.48
For coated/cover stock: GSM ≈ lbs X 2.71
For a more breakdown, you can review the table given below:
Coated & Text Stock in lbs | Text Stock in GSM | Coated Stock in GSM |
54 lb | ~80 | ~146 |
61 lb | ~90 | ~165 |
68 lb | ~100 | ~184 |
82 lb | ~121 | ~222 |
101 lb | ~150 | ~274 |
122 lb | ~180 | ~331 |
135 lb | ~200 | ~367 |
Now you can convert lb into gsm using this method. If you still have any questions, you can contact our experts through our chat support.
Please note: All calculated results will be approximate, meaning they will be closer to the accurate GSM you would measure using the scaling method.