Paint Calculator
Estimate paint required from wall area, openings, coverage and coats.
Enter your values
Use the fields below, then select Calculate. Your result appears immediately on this page.
How to use the Paint Calculator
Enter wall length, height, number of similar walls, total area of doors/windows, paint coverage and number of coats.
Formula / calculation logic
Net wall area = Length × Height × Walls − Openings. Paint needed = Net area × Coats ÷ Coverage per litre.
Worked example
Four 5 m × 2.5 m walls, no openings, two coats and 10 m²/L coverage require about 10 L.
Important notes
Actual coverage varies with surface porosity, paint type, color change, application method and waste. Buy according to manufacturer guidance and practical allowance.
Frequently asked questions
Should I subtract doors and windows?
Yes. Enter their combined area as openings if you do not plan to paint them.
Is the result exact?
No. It is a planning estimate based on the coverage value you provide.