AlienCalc — Real tools, slightly extraterrestrial

Paint Quantity Calculator

Estimate the amount of paint needed to paint a room. Enter the room dimensions, the number of coats desired, and the paint coverage to get the number of liters required.

Enter the room length in meters
Enter the room width in meters
Enter the ceiling height in meters
Number of paint coats to apply (1 to 5)
Paint coverage in m² per liter (check the can label)

Paint quantity needed

Wall surface

-

Total surface (with coats)

-

Liters needed

-

How to estimate paint quantity?

  • Coverage – Average paint coverage is 10 to 12 m² per liter. Always check the can label for the exact coverage rate of your product.
  • Number of coats – Generally, 2 coats are recommended for optimal results. On dark backgrounds or raw surfaces, a 3rd coat may be necessary.
  • Surface calculation – Wall surface is calculated as perimeter × height. Remember to subtract doors and windows (approximately 1.5 m² per door and 1.5 m² per window).

Practical tips

Always allow an extra 10% of paint for touch-ups and waste. On porous surfaces (new plaster, filler), apply a primer first to reduce absorption and improve the coverage of the topcoat. A standard room (3 m × 4 m × 2.5 m) requires about 5 to 6 liters for 2 coats.