Paint Calculator
Free paint calculator. Enter room size to get the gallons, quarts and litres of paint you need for your walls and ceiling, accounting for doors, windows and coats.
About the Paint Calculator
Estimate wall paint from room dimensions, coats and door or window deductions. The calculation uses fixed coverage and opening-size assumptions, so check the paint label and your actual surfaces. Switch between imperial and metric estimates; this is a purchasing estimate rather than an exact paint requirement.
Features
- Room dimensions
- Coat count
- Door and window deductions
- Imperial and metric estimates
How to use this tool
The Paint Calculator works right in your browser — no signup, no installation. Follow these steps:
- Enter the room length, width and wall height in feet.
- Choose whether to paint the ceiling and how many coats you plan.
- Enter the number of doors and windows to subtract.
- Read off the gallons, quarts and litres of paint to buy.
Frequently asked questions
How does this tool work?
Estimate wall paint from room dimensions, coats and door or window deductions. The calculation uses fixed coverage and opening-size assumptions, so check the paint label and your actual surfaces. Switch between imperial and metric estimates; this is a purchasing estimate rather than an exact paint requirement.
Using the results
The Paint Calculator estimates quantities from your measurements and the stated assumptions. Check dimensions, product coverage and project requirements before buying materials.