VolunaroSquare footage calculator
How the calculation works
- Shapes: enter each rectangle, circle or triangle with its dimensions. Mark a shape as a cut-out to subtract it.
- Area: rectangles are length × width, circles are π × radius², and triangles are base × height ÷ 2. We add them up and subtract the cut-outs.
- Units: the total is shown in square feet, whatever units you measured in. 9 sq ft make 1 sq yd.
Worked example
A 20 × 10 ft area plus an 8 × 6 ft extension, minus a 4 × 3 ft cut-out.
- Total area
- 236.0 sq ft
Default values and sources
| Value | Default | Type | Sources |
|---|
Limitations
- This tool adds up simple shapes. Split an irregular area into rectangles, circles and triangles, and subtract the parts that are not included.
- It measures the flat area of a surface as you entered it. Slopes, steps and walls need to be measured along their own surface. Real-estate square footage follows local rules that this tool does not apply.
Results are estimates for planning and ordering, not professional, engineering or legal advice. Confirm quantities, sizes and local building requirements with your supplier or contractor before you buy or build.