AtlasCalc🏗️ ConstructionbeginnerOffline
Paint Calculator
Estimate paint needed for walls, ceilings, or rooms.
Inputs
Enter your values below.
Result
Your answer appears here.
Enter values and press Calculate — the result appears here.
How it works
The formula behind this calculator.
area = perimeter × height; gallons = area / coverage; coverage ≈ 350–400 ft²/gal
- perimeter
- Total room perimeter in feet
- height
- Wall height
One gallon covers ~350–400 ft² of smooth wall. Textured surfaces need 10–20% more. Two coats is standard.
Example: 12×12 ft room, 8 ft walls: 96 ft perimeter × 8 ft = 768 ft² → ~2 gallons/coat
Ref: Paint manufacturers' coverage data
Tips
- 💡 One gallon covers ~350–400 sq ft of smooth wall. Textured surfaces need 10–20% more.
- 💡 Two coats is the norm. The second coat covers the missed spots and unifies the sheen.