About the Wall Area Calculator
Total wall area of a room or elevation with doors and windows deducted.
Also known as: wall square footage, surface area of walls, room wall area, paintable area.
How to use this calculator
- Enter calculate for, ceiling height, number of doors, area of each door and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
net area = perimeter × height − openings
Worked example
Using the values pre-filled in the calculator above:
- Calculate for: A whole room
- Room length = 5 m
- Room width = 4 m
- Ceiling height = 2.4 m
- Number of doors = 1
- Area of each door = 1.8 m²
- Number of windows = 2
- Area of each window = 1.5 m²
the calculator returns:
- Net wall area: 38.4 m²
- Gross wall area: 43.2 m²
- Openings deducted: 4.8 m²
- In square feet: 413.33