Paint Calculator Number of walls 1 2 3 4 First wall Wall length ft in Second wall Wall length ft in Third wall Wall length ft in Fourth wall Wall length ft in Room height ft in Number of doors Number of windows Are you painting the ceiling? Yes Ceiling area Ceiling length ft in Ceiling width ft in Number of coats of paint You are painting square feet. You will need approximately this much paint to finish your project: gallons quarts Apply for credit with us! Credit Application