Paint surface calculator
Enter your wall sizes, the coverage printed on the tin, and the number of coats. Results update as you type.
Add a row for each wall (or ceiling) you're painting. Use metres.
Doors, windows, or anything else you're not painting over. Enter the area in square metres.
No deductions - the whole wall area will be painted.
Coverage is what the tin says it covers with a single coat. UK emulsion averages about 12 m² per litre, but check your tin.
From the tin label, one coat.
2 for most jobs.
Updates as you type.
- Total wall area
- m²
- Net area to paint
- m²
- Area × coats
- m²
- Tins needed (exact)
- Order quantity
- m² deducted
coat(s)
Includes % wastage
Wall area is width × height for each wall, summed up. Deductions are subtracted to get the net area you're actually painting. Multiplying that by the number of coats gives the total coverage needed. Dividing by the tin's stated coverage tells you how many tins you need.
Manufacturer coverage figures are best-case on a smooth, already-sealed surface. Bare plaster, uneven textures, and dark base colours all drink more paint. 10% wastage is the usual minimum; bump it to 15-20% for a first-time paint job on bare plaster, heavily textured walls, or when covering a dark colour with a lighter one.
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