Wall Square Footage Calculator

Find the paintable/coverable wall area after removing windows and doors.

How the Math Works

The Wall Square Footage Calculator uses a straightforward formula to determine the usable wall area: net = length × height − openings. First, the total wall area is calculated by multiplying its length by its height. Next, the combined area of all openings (like doors, windows, or archways) is subtracted from this total. Each opening's area is individually measured as width × height (or length × height, depending on orientation), then summed to get the 'openings' value. This ensures the final result reflects only the surface available for painting, tiling, or other treatments.

Practical Applications

To use this calculator, measure the wall's total length and height, then multiply these dimensions to find the gross area. Next, measure each opening's dimensions (width and height) and calculate their individual areas. Add all opening areas together, then subtract this total from the gross wall area. This process is essential for projects like estimating paint quantities, calculating wallpaper rolls, or determining trim requirements, ensuring precise material purchases and avoiding waste.

Day-to-Day Use

This calculation simplifies everyday home improvement tasks, such as planning a room renovation or redecorating. By accurately measuring net wall area, you can budget for supplies like primer, paint, or wallpaper without overbuying. It’s also helpful for DIY enthusiasts installing baseboards or wainscoting, as it clarifies the exact surface to cover. For professionals, this tool streamlines project estimates and client consultations, making it a practical asset for both casual and commercial projects.

Worked example

20×8 ft wall minus 21 ft² of openings → 139 ft².

FAQ