Paint calculator
Litres and cans for your exact room: walls and ceiling, doors and windows deducted, coats included. Free, instant, no sign-up.
Enter your room's length, width and ceiling height and the litres appear here.
How the maths works
Wall area is the room's perimeter times ceiling height, minus about 1.7 m² per door and 1.4 m² per window. Coverage is banded at 16 m² per litre per coat, the standard for Australian washable acrylics, and litres round up into 4L and 1L cans the way you'd actually buy them.
Pick the colour with your eyes, not a swatch card
A 5cm swatch lies: light, room size and the floor's colour all change how paint reads on a full wall. The Design Studio renders real Dulux colours across a photo of your actual room, prices the paint alongside every other surface, and lets you compare two colours side by side before you commit a weekend to one.
How much paint do I need per square metre?
Australian washable acrylics cover about 16 m² per litre per coat. Two coats is standard, so allow one litre per 8 m² of wall. A typical 4 × 3.5m bedroom with 2.4m ceilings needs around 4-5 litres for the walls and 2 litres for the ceiling.
How many coats of paint do I need?
Two coats is the standard for a colour change on sound existing paint. Going dramatically lighter over a dark colour, or painting fresh plaster, often needs a dedicated primer or a third coat. A same-colour refresh can get away with one.
Do I subtract doors and windows when calculating paint?
Yes. A standard door is about 1.7 m² and an average window about 1.4 m². This calculator deducts them automatically, which stops you buying a whole extra can for area you'll never paint.
What does it cost to paint a room in Australia?
DIY, a typical bedroom runs $120-250 in quality paint and sundries. Professionally painted, expect roughly $250-400 per room for walls only, more with ceilings, trim and doors. Quality acrylic paint retails around $60-95 per 4L can in 2026.