A 4 × 3 m bedroom
Walls 2.5 m high plus ceiling, one door and two windows: 42.2 m²; two coats at 10 m²/L with 10 % extra: 9.28 L, i.e. 4 cans of 2.5 L.
Paint calculator
Enter the size of the room, the doors and windows, the number of coats and the coverage printed on the can: PRAXAO calculates the area to paint, the litres needed with a small margin, and how many cans to buy.
Result
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Results are provided for information. Check tax rates and legal requirements that apply to you.
How to use it
- Enter the room length, width and wall height.
- Tick the ceiling if you paint it too.
- Enter the number and size of doors and windows.
- Set coats, coverage (from the can) and can size, then read litres and cans.
Examples
Frequently asked questions
How do I calculate the wall area of a room?
Perimeter × height: 2 × (length + width) × height, minus doors and windows.
Where do I find the coverage?
On the can, in m² per litre per coat. It depends on the product and on the surface: porous or rough walls absorb more.
How many coats do I need?
Usually two. Plan for a primer or a third coat on new plaster, dark colours or strong colour changes.
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