Paint Coverage Calculator
Calculate how much paint you need for a room or wall area. Room dimensions or total area.
Paint Coverage
Typically 8-12 m² per litre for emulsion
Your Results
Room mode assumes 4 walls, deducts ~20% for windows/doors. Buy 10-15% extra.
What is a Paint Coverage Calculator?
A paint coverage calculator helps you estimate how much paint you need for a room or wall area. By entering room dimensions (or total wall area), number of coats, and the paint’s coverage rate, you can avoid buying too much or running out mid-project.
How Paint Coverage Works
The Formula
Paint Needed (litres) = (Total Area ÷ Coverage per Litre) × Number of Coats
Room Area Calculation
For a rectangular room: Wall Area = 2 × (Length + Width) × Height
We typically deduct about 20% for windows and doors.
Example
- Room: 4m × 3m × 2.5m
- Wall area: 2 × (4 + 3) × 2.5 = 35 m² (minus ~20% = 28 m²)
- Coverage: 10 m² per litre
- Coats: 2
- Paint needed: (28 ÷ 10) × 2 = 5.6 litres
Coverage Rates
| Paint Type | Typical Coverage |
|---|---|
| Emulsion (walls) | 8-12 m² per litre |
| Matt emulsion | 10-12 m² per litre |
| Gloss | 12-16 m² per litre |
| Primer | 10-15 m² per litre |
Check the tin—coverage varies by brand and product.
How Our Calculator Works
- Choose mode: Room dimensions or total area
- Enter dimensions or area: In metres
- Set number of coats: Usually 2 for walls
- Enter coverage: From the paint tin (typically 8-12 m²/L)
- Get result: Litres of paint needed
Tips
- Buy 10-15% extra for wastage and touch-ups
- Dark colours may need an extra coat
- Porous surfaces absorb more paint
Frequently Asked Questions
How much paint do I need for one room?
Use our calculator with room length, width, and height. A typical 4m × 3m × 2.5m room needs about 5-7 litres for 2 coats of emulsion.
What does coverage per litre mean?
It’s the area (in m²) one litre of paint will cover with one coat. Check your paint tin—it’s usually 8-12 m²/L for emulsion.
How many coats of paint do I need?
Most walls need 2 coats for even coverage. Dark colours or dramatic colour changes may need 3. Primer counts as a separate coat.