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Paint Calculator
Know exactly how many liters of paint to buy before going to the store.
Surface area is computed as the perimeter of the room times the wall height (2 × height × (length + width)), plus the ceiling when selected. Multiply by the number of coats and divide by the coverage of your paint (m²/L).
How it works
Surface area is computed as the perimeter of the room times the wall height (2 × height × (length + width)), plus the ceiling when selected. Multiply by the number of coats and divide by the coverage of your paint (m²/L).
Worked example
A 5 m × 4 m room with 2.5 m walls and 2 coats: walls = 2×2.5×(5+4) = 45 m², ceiling = 20 m², total 65 m² × 2 coats = 130 m² ÷ 10 m²/L = 13 liters.
Recommendations
- Choose paint with high coverage (10–14 m²/L) to reduce cost
- Subtract windows and doors: roughly −1.5 m² each
- Buy one extra liter to keep for touch-ups
Tips & advice
- Always stir the can before use and apply a primer coat
- Two thin coats last longer than one thick coat
- Use a roller for walls and a brush for corners and trim
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Paint Calculator
Know exactly how many liters of paint to buy before going to the store.
Use the calculatorInvoice Generator FAQs
Yes, all 20 home calculators are 100% free, private and run entirely in your browser. No account needed.
They use standard industry formulas. Always round up for materials and confirm with a professional for structural work.
The calculators use metric units (meters, liters, m³). Convert imperial measurements beforehand if needed.
No. Calculations happen instantly in your browser and nothing is sent to any server.
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