About the Irregular Land Area Calculator
Area of an irregular plot from its corner coordinates, using the surveyor’s shoelace formula.
Also known as: shoelace formula, polygon area calculator, irregular plot area, survey area calculator.
How to use this calculator
- Enter x coordinates (metres, in order), y coordinates (metres, in order).
- 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
A = ½ |Σ (xᵢ·yᵢ₊₁ − xᵢ₊₁·yᵢ)|
Worked example
Using the values pre-filled in the calculator above:
- X coordinates (metres, in order): 0, 40, 55, 30, 0
- Y coordinates (metres, in order): 0, 0, 30, 45, 25
the calculator returns:
- Area: 1,762.5 m²
- In acres: 0.43552
- In hectares: 0.17625
- In square feet: 18,971.4