🎨 Paint Calculator – Estimate Paint Needed for Walls & Rooms

Quickly find out how much paint you need for any surface with customizable options for coats, surface texture, and room dimensions.

Dimensions

ft
ft
ft
ft²
Total area of all doors and windows you won't be painting

Paint Settings

Typical coverage: 250 ft²/gal (1 coat) for oil-based on semi-rough

Cost Estimation

$ per gallon
Optional - leave blank if you don't want cost estimation

How to Use the Paint Calculator

  1. Enter wall or room dimensions
  2. Subtract any doors/windows from the total
  3. Choose the surface type and paint type
  4. Select number of coats and unit system
  5. View the total paint required and optional cost

Typical Paint Coverage

Surface Type Oil-Based (ft²/gal) Latex (ft²/gal) Notes
Smooth Walls 300-350 350-400 High efficiency
Semi-Rough Walls 220-270 280-330 Slightly reduced
Rough Walls 150-200 200-250 More absorption

Tips & Painting Advice

  • One coat is fine for retouching; always use two for new walls
  • Prime rough surfaces to improve coverage
  • Stir paint well and check viscosity for consistency
  • Buy extra 10-15% for touch-ups or errors
  • Oil-based paints cover less area but are more durable