Calculator
Paper weight calculator
A watercolor pack says 140 lb and the shop asks for grams. One factor does not fit every sheet: watercolor, text and bond paper sit on different scales.
Calculator form
How to
How to use
1
Choose the kind of paper
Watercolor and cover share one scale. Text and bond use others.
2
Enter the number on the pack
140 for standard watercolor, or 300 if you already have gsm and want pounds.
3
Check the direction
lb to gsm when you are buying metric paper. The reverse is for comparing an imported pack.
Examples
Sample calculations
Watercolor 140 lb
300 gsm
Pitfalls
Common mistakes
Mistake
Dividing every pound weight by the same factor → 20 lb bond is about 75 gsm, not the 300 gsm of watercolor.
FAQ
FAQ
Why is 140 lb equal to 300 gsm?
Watercolor and cover stock use the factor 300/140. Other papers use the factors listed in the form.
What is 90 lb watercolor in gsm?
About 193 gsm. Fine for studies. Heavy washes want 300 gsm.
Lock it in with practice
Open the free editor and apply the result — a short sketch beats more reading.