Drawing grid calculator
A grid carries proportions while your eye is still unreliable. Enter the reference size and how many cells you want across and down to get the size of one cell.
Calculator form
How to use
Read the image size
Width and height of the reference in pixels, from the file properties.
Choose the cell count
10×8 is enough for a portrait. More cells means more accuracy and more time.
Repeat the same grid
On your canvas the cells should keep the same proportions, even if the canvas is larger.
Sample calculations
1200×800 on a 10×8 grid
Each cell is 120×100 px
Common mistakes
Mistake
Forcing square cells on a wide photo → If the cells come out rectangular, draw them rectangular on the canvas too.
FAQ
How many cells should a beginner use?
Start with 8–12 along the long side. Go finer only for a close-up of a face.
Do the cells have to be square?
No. What matters is that the cell proportion matches on the reference and on your drawing.
Lock it in with practice
Open the free editor and apply the result — a short sketch beats more reading.