COMPARE TOOLS
Paint quantity vs paint cost: plan both parts of a project
The quantity question is “how much paint?” The cost question is “what will it cost at my local prices?” Measure first, then price the amount you expect to buy.
Start with wall area
For a rectangular room measuring 12 ft by 12 ft with 8 ft high walls, the wall perimeter is 2 × (12 + 12) = 48 ft. Wall area before subtracting doors and windows is 48 × 8 = 384 sq ft. This example excludes the ceiling.
Turn area into paint quantity
For two coats, estimated coverage area is 768 sq ft. At an illustrative 350 sq ft per gallon, that is 768 ÷ 350 ≈ 2.2 gallons before waste or extra coverage. If you buy only whole gallon cans, you would plan for at least three. Real coverage changes with surface and paint; use the paint quantity calculator with your room measurements and product coverage.
Estimate the purchase
At an illustrative $35 per gallon, three gallon cans would cost $105 before tax, primer, tape, rollers or labor. Use the paint cost calculator with the prices you actually find. Compare pack sizes and include any supplies you intend to purchase.