Paint Calculator
Estimate paint quantity (liters + cans) and cost for your room's walls.
Practical calculatorGeneral editable assumptionsGlobal-readyInteractive chart
Last updated: 2026-06-03
This calculator uses generic assumptions. Use advanced mode to override them for a more accurate result.
Inputs
Formula transparency
Source: defaultliters = (net area × coats / coverage) × (1 + waste)
How to use it
- Enter wall length, height, and number of walls.
- Set coats and coverage; deduct doors/windows in advanced mode.
- Add price per liter for a cost estimate.
Example
- A 4m × 3m × 4-wall room, 2 coats at 10 m²/L needs about 9.6 L.
What the result means
Liters needed includes your waste margin; cans round up to whole containers to buy.
Common mistakes
- Forgetting the second coat.
- Not deducting large doors and windows.
- Ignoring the can's stated coverage.
Limitations
- Rough surfaces and primers change consumption.
- Estimate only.
Frequently asked
- Default coverage?
- We assume ~10 m²/L; adjust to your paint can.
- How to deduct doors/windows?
- Sum their areas (L×W) and subtract in advanced mode.
- Does it include the ceiling?
- No — add the ceiling as an extra wall with its area if needed.
- How many coats?
- Usually two; light over dark may need more.
- Is it exact?
- It's an estimate; buy a small margin for touch-ups.
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Results are estimates and not professional advice. Verify important decisions with a qualified professional.