eTools Painting

In general 1 gallon of paint covers 350 square feet.
Subtract 20 square feet for a door and 15 square feet for a window.

Ceiling paint estimator

Use the following formula to estimate the amount of ceiling paint you need. Double the result if the ceiling requires two coats.
1. Multiply the length of the ceiling times its width to find its area. 14*20=280 square feet
2. Divide that number by 350 (the estimated square feet covered per gallon) to figure out how many gallons of paint you need. 280/350=.8
For this example, you want to buy 1 gallon of ceiling paint for a single coat.

Wall paint estimator

Use the following formula to estimate the amount of wall paint you need. Double the result if the walls require two coats.
1. Add together the length of each wall. 14+20+14+20=68 feet
2. Multiply the sum by the wall height, to find the total wall area. 68*8=544 square feet
3. Subtract 20 square feet for each door (20*2=40) and 15 square feet for each window (15*2=30) to find the actual amount of wall area you're painting. 544-70=474 square feet
4. Divide this figure by the paint coverage (350 square feet per gallon), and the result is the number of gallons to purchase.

Calculator Inputs

Ceiling paint estimator

Ceiling Width:
Ceiling Length:

Wall paint estimator

Room Width:
Room Length:
Room Height:
Door & Window Square Ft.:
Add 8% to 10% as waste:

Calculator Results:
Number gallon of ceiling paint needed:  
Number gallon of wall paint needed:  

Important Disclaimer: This calculator is provided for general information and illustration purposes only; the results are to be used only as estimates and are not intended as definitive advice or as a resource applicable to any specific circumstance and should not be relied upon or used as such.