Paint Coverage Calculator
Figure out how many gallons of paint you need before you head to the store. Enter your room dimensions or total square footage, select the number of coats, and deduct doors and windows for an accurate paint estimate.
Enter Your Details
Full Breakdown
Gross Wall Area
Deductions (doors/windows)
Net Paintable Area
Number of Coats
Total Coverage Needed
Exact Gallons
Gallons to Buy
How to Use This Calculator
- Choose Room Dimensions or Total Square Footage input mode.
- Enter measurements, number of coats (2 is standard), and deductions.
- Click "Calculate Paint" to see gallons needed.
- Standard deductions: doors = 21 sq ft, windows = 15 sq ft.
The Formula
Gallons = (Net Area × Coats) ÷ 350
Standard interior latex paint covers approximately 350 square feet per gallon. Net area = total wall area minus doors (21 sq ft each) and windows (15 sq ft each). Results are rounded up to the nearest gallon.