Paint Calculator
Calculate how much paint to buy. Enter the total wall area (or room dimensions), subtract doors and windows, choose the number of coats, and get liters and cans.
Enter your values
Result
Porous or new surfaces absorb more paint; budget ~10% extra for touch-ups.
How to use
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Save ⟶How to use the Paint Calculator
- 1Enter room length (m) in the form on the left.
- 2Fill in the remaining fields — the result updates automatically as you type.
- 3Review the highlighted result and the supporting breakdown on the right.
- 4Use Copy, Share or Print to save or send your result.
Getting paint quantities right
Wall area = perimeter × height, minus doors (~1.9 m² each) and windows (~1.5 m² typical). Multiply by coats and divide by the paint's coverage rating — usually 9–12 m² per liter for emulsion, less for primers on porous surfaces.
Two coats is the norm for color changes and washable finishes. Dramatic color changes (dark over light or vice versa) may need a tinted primer plus two topcoats — cheaper than three coats of premium paint.
Frequently Asked Questions
▸How much area does 1 liter of paint cover?
Typically 9–12 m² per coat on smooth, sealed walls. Rough or porous surfaces reduce coverage by 20–30%. Use the figure printed on your paint can.
▸Do I really need two coats?
Usually yes — one coat rarely gives even color and full washability, especially over a different color. The exception is repainting with the identical shade.