MEASURE · PLAN · MAKE IT COUNT
Paint calculator: how much paint do I need?
Estimate paint and whole tins for your walls.
Not sure of your wall area? Measure a room
For four walls in a rectangular room. Use net area directly for irregular spaces.
Metric units as labelled. Prices, where used, are in EUR.
Method and limits
Net area × coats ÷ coverage per coat, plus your purchase allowance. Subtract openings once. Add the ceiling only if it uses the same product and coverage.
Worked example
With the editable starting values: 6.6 litres. 2 tins of 4 l
- Net paint area (m²): 30
- Coats: 2
- Coverage per coat (m²/l): 10
- Allowance (%): 10
- Tin size (litres): 4
Frequently asked questions
Are these starting values recommendations?
No. They are editable examples. Use your own measurements and the product label or quoted specification.
What should I check before using the result?
Net area × coats ÷ coverage per coat, plus your purchase allowance. Subtract openings once. Add the ceiling only if it uses the same product and coverage.
Are units and prices converted automatically?
No. These tools use the metric units shown next to each field. Monetary inputs and results are in EUR; enter the relevant EUR tariff or quote. No currency conversion or live prices are applied.
PLANNING SOMETHING BIGGER?
Refresh a room
Connect the related calculations in one materials summary.
A 12 m² room does not mean 12 m² of walls
Wall area comes from the perimeter multiplied by wall height, minus doors and windows. Add the ceiling only when you will paint it with the same product. Floor area alone cannot tell you the amount of paint.
| Room floor | Surfaces | Net paint area | Litres with reserve | Whole tins |
|---|---|---|---|---|
| 4 × 3 m (12 m²) | Walls only | 33 m² | 7.26 l | 2 × 4 l = 8 l |
| 4 × 3 m (12 m²) | Walls + ceiling | 45 m² | 9.9 l | 3 × 4 l = 12 l |
| 5 × 4 m (20 m²) | Walls only | 42 m² | 9.24 l | 3 × 4 l = 12 l |
The 4 × 3 m examples subtract 2 m² of openings; the 5 × 4 m example subtracts 3 m². The reserve is added once to total paint, then tins are rounded up.
Three details that change your purchase
- Use coverage per coat from the product label. Do not treat a stated two-coat coverage as one-coat coverage.
- Surface condition and the product affect coverage and coat count. The calculator cannot inspect your wall.
- Paint types are not interchangeable: calculate wall paint, ceiling paint and primer separately when they use different specifications.
Manufacturer references
Dulux — product-specific coverage and coats · Bruguer — ceiling paint technical information (Spanish)