Skip to content

Paint calculator

How many gallons or liters of paint a room needs, minus doors and windows, for the coats you plan.

Favorite

Results

Paint (US gallons) 1.73 gal

How it works

paint = wall area × coats ÷ coverage

The walls of a room add up to its perimeter (2 × length + 2 × width) times the wall height. Doors (about 20 ft² / 1.9 m² each) and windows (about 15 ft² / 1.4 m² each) are taken off. Multiply by the number of coats and divide by the coverage on the can, typically 350–400 ft² per gallon (about 9 m² per liter).

  1. Wall area: perimeter × height 2 × (3.6576 + 3.048) × 2.4384 = 32.7 m²
  2. Take off doors and windows 32.7 − 1 × 1.858 − 2 × 1.394 = 28.06 m²
  3. Times coats ÷ coverage 28.06 × 2 ÷ 8.589835 m²/L = 6.53 L
  4. In US gallons 6.53 ÷ 3.785411784 = 1.73 gal

Printed from rocketcalc.io/construction/paint