The Paint Needed for a Wall or any rectangular area calculator computes the number of gallons of paint and primer needed to cover a rectangular area.
INSTRUCTIONS: Choose units and enter the following:
- (L) Length
- (H) Height
- (PC) Coverage per Gallon (area covered by one gallon: default 400ft2)
- (CT) Coats of Paint
- (WD) Number of Windows
- (DR) Number of Doors
Wall Paint (WP): The calculator returns the gallons of paint or primer needed to cover the wall area. The calculator also returns the surface area of the wall in square feet. However, these answers can be automatically converted to compatible units via the pull-down menu.
To estimate the cost of paint or primer for a wall,CLICK HERE.
The Math / Science
The surface area of a wall (blue in diagram) is based on the length and height. The mean square feet for a gallon of quality paint is 400 ft2 . Primer covers 200 ft2. The gallons of paint and primer are the total surface area divide by the square feet per gallon.
To compute the surface area of a wall,CLICK HERE. The surface area is then reduced by 15 ft2 for each window and 21 ft2 for each door.
Paint Calculators:
- Paint for a Room: computes the number of gallons of paint or primer needed to paint an entire room, the four walls and ceiling and also for just the walls.
- Paint for a Wall: computes the number of gallons of paint or primer needed to paint a wall or any rectangular area (wall or ceiling).
- Exterior Paint for a House: computes the number of gallons of exterior paint for a gabled building like a common house.
- Cost to Paint or Primer a Room: (CLICK HERE)
- Cost to Paint a Wall: (CLICK HERE)
- Cost to paint or prime a ceiling: CLICK HERE
- Paint Pricing Survey
Paint Pricing Survey Data
One should use the pricing for paint or primer that can be bought locally since prices may vary. However, the following prices are recent U.S. dollar costs for one gallon of paint or primer in the United States:
- Paint Pricing Survey date: 7/29/22
- Paint Price Survey Source (online): HomeDepot
- Price of premium (high quality) paint: $61.94 USD
- Price of medium grade paint: $48.98 USD
- Price of economy paint: $26.98 USD
- Price of primer: $19.98 USD
Wall and Room Calculators
- Number of gallons to paint or primer a room.
- Cost to paint or prime a room.
- Surface area of the interior walls of a room
- Surface area of the interior walls and ceiling of a room.
- Floor area of a room
- Volume of a room
- Energy (BTUs/hr) needed to heat a room
- Number of Studs in a Room
- Number of drywall sheets needed for a room
- Surface area of a Wall
- Surface Area of a Ceiling