How Much Paint Do I Need?

Enter your room details below. We'll tell you exactly how many gallons to buy.

Room Dimensions

Length (ft)

Width (ft)

Height (ft)

Walls to Paint

Wall A0.0×0.0 ft = 0.00 sq ftWall B0.0×0.0 ft = 0.00 sq ftWall C0.0×0.0 ft = 0.00 sq ftWall D0.0×0.0 ft = 0.00 sq ftCeiling0.0×0.0 ft = 0.00 sq ft

Doors & Windows

Doors

Windows

Surface & Method

Surface Type

Application Method

Paint Details

Number of Coats

Coverage (sq ft / gallon)

Standard: 350 — no need to change unless your paint can says otherwise

Enter your room details and click Calculate.

How This Paint Calculator Works

Our calculator computes each selected wall area individually (L × H or W × H), subtracts door and window areas, then applies surface and method factors. Divide net area by coverage rate and multiply by coats.