Paint Coverage & Gallon Calculator
Eliminate guesswork and avoid costly paint overages. Input your wall dimensions, specify door and window cutouts, choose your number of coats, and get instant recommendations in gallons, quarts, and liters.
How to Use Paint Calculator
Input Wall Dimensions
Enter the length and height of each wall or total room perimeter.
Deduct Openings
Specify the number of doors and windows to automatically subtract non-painted square footage.
Select Coats
Choose 1, 2, or 3 coats (2 coats recommended for dramatic color changes).
About Paint Calculator
One standard gallon of quality interior wall paint covers approximately 350 to 400 square feet with one coat on a smooth, primed surface. Textured drywall, unprimed masonry, or porous plaster will reduce coverage to approximately 250 to 300 square feet per gallon.
Supported Formats
Key Features
- Automatic door (21 sq ft) and window (15 sq ft) square footage deduction
- Supports 1, 2, or 3 coats with separate primer option
- Standard 350-400 sq ft per gallon architectural paint coverage benchmark
- Outputs in Gallons, Quarts, and Metric Liters
- Estimates for ceiling painting and baseboard trim
Frequently Asked Questions
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