Paint Cost Calculator
Use the paint cost calculator below to get an instant material and installed price range for your project. To estimate paint, find the wall area (perimeter × height), subtract about 21 sq ft per door or window, multiply by the number of coats, and divide by 350 (sq ft per gallon). A 12×12 ft room with 8 ft walls needs about 2 gallons for two coats, costing roughly $50–$120.
Your measurements
Each opening subtracts ~21 sq ft of wall.
Enter your measurements
Fill in the fields to see your estimate.
Paint needed by room size
Gallons for two coats on a room with 8 ft walls, minus two openings.
| Room size | Wall area | Gallons (2 coats) | Paint cost |
|---|---|---|---|
| 10 × 10 ft | ~318 ft² | ~2 gal | $50 – $120 |
| 12 × 12 ft | ~342 ft² | ~2 gal | $50 – $120 |
| 15 × 15 ft | ~438 ft² | ~3 gal | $75 – $180 |
| 20 × 20 ft | ~598 ft² | ~4 gal | $100 – $240 |
What affects paint cost
- Project size — larger painting jobs lower the cost per unit but raise the total.
- Material grade — premium products cost more but often last longer.
- Labor rates — local wages and demand swing installed prices significantly.
- Region — prices vary by state and metro (see local cost pages below).
- Site access & prep — removal of old material and difficult access add cost.
- Season — booking in the off-season can cut labor pricing.