Paint Calculator

Estimate paint needed from room dimensions, openings, coverage, and coats.

Length (m)Width (m)Imported wall perimeter (m)Wall height (m)Doors and windows (m²)CoatsCoverage (m² per litre)Allowance (%)

Estimate only

This estimate uses the dimensions and allowance you enter. Measure the actual area and check the product label before buying paint.

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Paint Calculator estimates the total litres of paint required for room walls based on dimensions, doors, windows, coverage rates, and coat counts.

Enter room wall length, width, and wall height.
Specify counts and sizes of doors and windows to subtract non-painted wall areas.
Select paint coverage rate per litre (printed on product label) and coat count.
Click Calculate to view required paint litres.

Dimensions: 4m x 4m room, 2.5m high, 1 door, 1 window, 2 coats Result: 6.51 litres of paint required.

How are doors and windows subtracted from wall area?

Standard door (approx 2m²) and window (approx 1.5m²) surface areas are multiplied by counts and subtracted from gross wall area.

Should I buy extra paint for touch-ups?

It is recommended to round up to the nearest standard paint tin size (e.g. 2.5L or 5L tin) to keep extra paint for future touch-ups.

Decorating