Paint calculator

Most interior paints cover 350–400 square feet per gallon per coat (10–12 m² per liter). Porous or textured surfaces and strong color changes reduce coverage, so use the lower figure when in doubt.

Two coats is the standard for a uniform finish. One coat only works when repainting with the same or very similar color; covering a dark color may take three.

Yes. Add up the area of all openings and enter it in the openings field — a standard door is about 20 sq ft (1.6 m²) and an average window 15 sq ft (1.4 m²).

Round up to whole cans and keep the remainder for touch-ups. Paint from a later batch can differ slightly in shade, so buying everything at once is safer.