Map Area Calculator
Measure an area from GPS points or map coordinates (latitude and longitude).
About the Map Area Calculator
Paste the corner coordinates of a plot, one latitude, longitude pair per line, in order around the boundary. The calculator gives the area in square metres, square feet and acres, and the perimeter.
List the corners in order around the boundary. The calculator projects the points onto a flat, equal-area plane centred on the plot (accurate for plots up to several kilometres across) and applies the shoelace formula; the perimeter uses great-circle (haversine) distances. Phone GPS is typically accurate to 3–5 m, so small plots can be off by a noticeable percentage.
The formula
Shoelace: A = ½ |Σ (xᵢ yᵢ₊₁ − xᵢ₊₁ yᵢ)|
Worked example
Four corners of a plot in Bengaluru, about 100 × 108 m
- Area: 10,844 m² (116,723 ft²)
- = 2.68 acres
- Perimeter 416.9 m
Questions people ask
Do the points need to be in order?
Yes, going around the boundary, not criss-crossing.
How accurate is it?
As accurate as the points; survey-grade GPS is centimetre-level.