paint calculator
Calculate how many litres or gallons of paint you need. Add multiple rooms. No sign-up.
Rooms / surfaces
Room nameLengthWidthHeight
Options
Paint coverage guide
| Rough / textured | ~10 m²/L |
| Standard wall | ~12 m²/L |
| Smooth / primer | ~14 m²/L |
| Ceiling paint | ~16 m²/L |
| Standard door | ~1.8 m² |
| Standard window | ~1.4 m² |
| 1 US gallon | = 3.785 L |
| 1 gallon covers | ~37 m² (1 coat) |
Tips
Always add 10% extra for waste, touch-ups and colour matching. Buy the same batch number — colours vary slightly between batches.
Two thin coats always give better results than one thick coat. Let the first coat dry fully before applying the second.
Can sizes to look for
| Sample pot | ~250 ml |
| Small tin | 1 L |
| Standard | 2.5 L or 4 L |
| Large | 10 L |
| Trade | 15 L or 20 L |
FAQ
Should I include the ceiling?
Add the ceiling as a separate "room" using the same length × width as the floor, with a height of 0 (just use length and width as the ceiling area).
How many coats do I need?
2 coats for most walls. 3 coats when covering dark colours or painting over raw plaster. 1 coat for a refresh over the same colour.
Is my data stored?
No — all calculations run in your browser.