Calculate paint quantity for any room or surface. Enter length, width, height, and number of coats. Accounts for doors, windows, and wastage. Works in metres and feet.
Measure wall area (2 x (length + width) x height) plus ceiling (length x width). Subtract doors (1.89 sq m each) and windows (1.2 sq m each). Divide by paint coverage per litre, multiply by coats, and add 10% wastage.
A 12x12 ft (3.65x3.65m) room with 9ft ceilings has about 45 sq m of wall area. At 12 m/L with 2 coats: 45 x 2 / 12 = 7.5 litres plus wastage gives roughly 8.3 litres.
Standard interior emulsion covers 10-12 sq m per litre. Premium paints cover 12-16 sq m. Exterior paints cover 8-10 sq m. Check the manufacturers label for the specific product.
New or bare walls need 1 coat of primer plus 2 finish coats. Repainting a similar colour needs 2 coats. Covering dark paint with a light colour may need 3 coats.
Yes. A standard door is approximately 1.89 sq m and a window 1.2 sq m. This calculator automatically deducts them from your total area.
Measure total external wall area, subtract all openings. Exterior masonry paint covers 4-8 sq m per litre as rough surfaces absorb more. Add 15% wastage for uneven surfaces.