Calculate the paint for a room
Enter the room dimensions. The tool subtracts the doors and windows, multiplies by the number of coats and rounds up to the containers sold in stores.
No account needed. The calculation is done in your browser: nothing is sent.
How it is calculated
Wall area: the perimeter of the room multiplied by the height, minus 1.7 m² per door and 1.5 m² per window (average values). The ceiling is added if you tick the box.
The starting coverage is 10 m² per litre. It changes with the paint and the surface: a new or textured wall absorbs more. The exact value is printed on the can; correct it in the field.
A room that is not rectangular is easier to work out on a plan: draw it to your measurements and the perimeter shows by itself.
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