Home & Cooking
Paint Calculator
Estimate wall area and gallons needed for a room.
Your inputs
Adjust the values
Door and window deductions use common estimates of 21 ft² and 15 ft². Buy enough for the selected number of coats.
Whole gallons to buy
3
About this tool
A straightforward paint calculator
Estimate wall area and gallons needed for a room. Room perimeter times wall height gives gross wall area; common opening deductions, coat count, and coverage determine paint volume.
Surface texture, application method, color change, spillage, and manufacturer guidance can change actual coverage. Inputs are processed in your browser, and changing a value updates the result immediately.
How it works
Use the Paint Calculator in three steps
- 1Enter your values
Enter room dimensions, doors, windows, coats, and the paint’s coverage per gallon.
- 2Check the setup
Choose the units or calculation mode that matches your situation.
- 3Use the result
See paintable area, coated area, exact gallons, liters, and whole gallons to purchase.
Common questions
Paint Calculator FAQ
How does the Paint Calculator work?
Room perimeter times wall height gives gross wall area; common opening deductions, coat count, and coverage determine paint volume.
What information do I need?
Enter room dimensions, doors, windows, coats, and the paint’s coverage per gallon.
How accurate is the result?
Surface texture, application method, color change, spillage, and manufacturer guidance can change actual coverage.