Paint Calculator
Calculate how much paint you need for your room
Don't buy too much or too little paint. This calculator estimates exactly how many gallons or liters you need based on your room dimensions.
Calculator Inputs
Sum of all wall widths
Standard door size subtraction
Standard window size subtraction
Results
Enter values above to see your results
How It Works
We calculate the total wall area, subtract typical areas for doors and windows, and multiply by the number of coats. Standard coverage is 350 sq ft per gallon (or ~9-10 sqm per liter).
Tips & Best Practices
- •Always buy a little extra for touch-ups.
- •Textured walls may require 10-20% more paint.
- •Darker colors covering lighter ones may need 3 coats.
Frequently Asked Questions
How much does a gallon of paint cover?
A standard gallon of paint covers approximately 350 to 400 square feet with one coat.
Guides & Articles
Home Renovation Estimating: Paint, Tile, and Wallpaper Math
Renovations always go over budget. Why? Poor estimating. Learn how to calculate material needs including waste factors and pattern repeats.
The Ultimate DIY Concrete Guide: Math, Mixes, and Mistakes
Concrete is expensive and unforgiving. Learn how to calculate cubic yards, handle slab depth variances, and avoid the dreaded 'cold joint'.
Stop Buying Too Much Concrete: A Guide to Estimating
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