Interior Paint Cost & Gallons Calculator
Estimate how many gallons of paint you need and what it will cost — for one room or your whole house.
Painting a room? This calculator does the math the pros do — wall area, door and window subtractions, coverage per gallon, and number of coats — so you walk into the store knowing exactly what to buy.
Interior paint estimator
- Paint$96
- Supplies (tape, rollers, drop cloth)$35
- Estimated total (DIY)$131
Hiring a pro? Add roughly $1.50–$4.00/sq ft for labor depending on prep work and trim detail.
Frequently asked
How many square feet does a gallon of paint cover?
About 350 sq ft per coat for smooth interior walls. Textured surfaces, primer, and bold color changes can drop coverage to 250 sq ft.
Should I always use 2 coats?
For repaints in a similar color, 1 coat is usually fine. For color changes, light over dark, or new drywall, 2 coats plus primer is the safe answer.
How much does a pro charge to paint a room?
Most painters quote $1.50 – $4.00 per square foot of wall area, including labor, prep, and basic materials.