Room Paint Calculator – Estimate Paint for Any Room
Planning to repaint a room? Get an exact paint quantity estimate for any room size — walls, ceiling, and trim — in seconds.
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How to Calculate Paint for a Whole Room
Calculating paint for a full room means working out the total paintable wall area — all four walls — then accounting for the ceiling, doors, and windows. Our room paint calculator simplifies this to a single step: enter your room dimensions and get an instant litre estimate.
For a standard rectangular room, total wall area = (2 × length + 2 × width) × ceiling height. Subtract doors (~1.8 m² each) and windows (~1.4 m² each). Divide by your paint's coverage rate and multiply by number of coats.
Room-by-Room Paint Estimates
Bedroom (3.6m × 3.6m, 2.4m ceiling)
Total wall area: 34.6 m². After 1 door and 2 windows: ~30 m². Two coats at 10 m²/L = 6 litres. Buy 7 litres including buffer.
Living Room (5m × 4m, 2.7m ceiling)
Total wall area: 48.6 m². After 1 door and 2 windows: ~44 m². Two coats at 10 m²/L = 8.8 litres. Buy 9–10 litres.
Kitchen (3m × 3.5m, 2.4m ceiling)
Total wall area: 31.2 m². After deducting above-cabinet areas and 1 window: ~20 m². Two coats = 4 litres.
Bathroom (2.5m × 2m, 2.4m ceiling)
Total wall area: 21.6 m². After 1 door and 1 window: ~18 m². Two coats = 3.6 litres. Use moisture-resistant bathroom paint.
Hallway (1.2m × 4m, 2.4m ceiling)
Total wall area: ~25 m². After 2 doors: ~22 m². Two coats of durable scrubbable paint = 4.4 litres.
Don't Forget the Ceiling
If you're painting the ceiling too, calculate its area separately. For a 3.6m × 3.6m room, ceiling area = 13 m². One coat of flat white ceiling paint at 10 m²/L = about 1.3 litres. Ceiling paint is usually applied in a single coat with flat/matte white.
Tips for Painting a Full Room
Paint ceilings first, then walls, then skirting boards and trim
Use a roller for large flat areas and a brush for edges and corners
Apply two coats for coverage — allow 2 hours drying time between coats
Use low-VOC paint in enclosed rooms for better indoor air quality
Tape off skirting boards and door frames before painting walls
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