Free Paper GSM Calculator
Measure the approximate GSM of paper by weighing a known number of sheets and entering their actual dimensions.
Calculator Inputs
How to calculate paper GSM from a weighed sample
GSM means grams per square metre. This calculator estimates paper GSM from the measured size of one sheet and the combined weight of several identical sheets.
- Select the measurement unit. Choose millimetres, centimetres, or inches.
- Measure one sheet. Enter its actual width and height using the selected unit.
- Weigh a sample. Enter the number of identical sheets and their combined weight in kilograms. A larger sample normally reduces scale-rounding error.
- Read the result. The calculator converts the dimensions to square metres and shows the approximate GSM.
For example, 100 A4 sheets measuring 210 × 297 mm and weighing 0.499 kg produce an estimate of approximately 80.01 GSM.
Understanding the result
The result is a practical estimate, not a laboratory certificate. Scale precision, paper moisture, coating, and variation between sheets can affect the measured GSM. Use identical, dry sheets and an accurately calibrated scale for a better estimate.
Paper GSM calculator questions
How is paper GSM calculated from weight?
Divide the sample weight in grams by the total area of all weighed sheets in square metres. The result is grams per square metre, or GSM.
Can I enter paper size in millimetres, centimetres, or inches?
Yes. Select the measurement unit first, then enter the actual width and height of one sheet in that unit.
Why should I weigh multiple sheets?
Weighing multiple sheets reduces the effect of scale rounding and usually gives a more reliable GSM estimate than weighing one sheet.
Is the calculated GSM exact?
It is an estimate based on the entered size and weight. Scale accuracy, moisture, coating, and variation between sheets can affect the result.