Paint Coverage Calculator
Enter the painting area, number of coats and coverage per litre to estimate the total paint needed for renovation purchasing.
Input Data
Results
At a glance:Total paint = area × coats ÷ coverage per litre × (1 + waste%). Coverage depends on the paint, substrate roughness and method; waste covers edges and tool residue. Dark over light or new absorbent walls need one or two extra coats. This calculator counts paint only, excluding primer (sealer) and filler. Buy whole cans and keep a little for touch-up.
Formula
Total = area × coats ÷ coverage × (1 + waste%)
Cans = ⌈total / 5⌉
$$V = \frac{A\, n}{c}(1+w)$$$$k = \left\lceil V/5 \right\rceil$$How to Use
- Enter the painting area (m²).
- Enter the number of coats and coverage per litre.
- Set the waste%.
- The tool outputs the total paint and suggested 5 L cans.
Case Studies
Room walls
30 m², 2 coats, 10 m²/L, 10%.
About 6.6 L total, buy 2 × 5 L cans.
Ceiling repaint
40 m², 3 coats, 9 m²/L, 12%.
About 14.9 L total, buy 3 × 5 L cans.
FAQ
How to set coverage?
Check the can label (m²/L); rough walls, spraying or porous substrates lower it, so use a conservative value.
Should I deduct doors and windows?
Deducting large doors/windows saves paint, but frames and trims use paint too, partly offsetting — a rough estimate can skip it.
Related Tools
References
Content review: Calculatorism Editorial Team. Results are for reference only; please refer to the relevant authorities for the official figures.