Primer Calculator

LengthHeightWidth

How to measure

Measure the length and width of the floor and the height of the walls, then count the doors and windows.

Room size
Doors and windows
Primer

Check the label on the can. Porous surfaces such as new drywall or bare wood soak up more.

Primer needed

1.47 gallons

Buy 1 gallon + 2 quarts

Wall area384 sq ft
Doors and windows−50 sq ft
Paintable area334 sq ft
Area to cover (1 coat)334 sq ft
Waste allowance10 %

At 250 sq ft per gallon. Gallons are rounded up to whole cans, with quarts for the remainder.

See the formula, sources and worked examples on Matholio