Paint calculator
Work out how much paint you need for a room, from the coverage on the tin.
Uses only the sizes you enter.
Result
At 12 square metres a litre, 2 coats take 5.017 litres of paint: 3 tins of 2.5 litres.
litres of paint
| Area to paint | 30.1 m² |
|---|---|
| Tins | 3 tins |
Show the workings
| Step | Sum | Answer |
|---|---|---|
| Wall area | 14 m × 2.4 m | 33.6 m² |
| Less doors, windows and anything unpainted | 33.6 − 3.5 | 30.1 m² |
| Area to cover, 2 coats | 30.1 × 2 | 60.2 m² |
| Paint | 60.2 m² ÷ 12 m² a litre | 5.017 litres |
| Tins | 5.017 ÷ 2.5 litres a tin, rounded up | 3 tins |
Where the figures come from
This sum uses only the numbers you entered.
How much paint do I need?
- Add up the length of the walls. A room 4 m by 3 m has 4 + 3 + 4 + 3 = 14 m of wall.
- Multiply by the height. At 2.4 m high that is 33.6 m².
- Take off doors and windows. Measure each and add them up.
- Multiply by the number of coats.
- Divide by the coverage on the tin, in square metres per litre.
Coverage differs a lot between paints and is printed on every tin, so the calculator asks for it. New plaster, dark colours under light ones and rough surfaces can all take more: the tin or the maker's website says when to allow for that.