Area Calculator — Measure Polygon Area on a Map
Draw a polygon or rectangle on the map; instantly find the land area in m², km², hectares, donum, and acres, and the perimeter in meters/km.
Drag the shape to edit it.
Manual Coordinate Input
Unit Note
1 donum = 1,000 m², 1 hectare = 10,000 m² = 10 donum. The area is computed with a geodesic formula; cadastral/legal measurement requires field work.
Related Tools
Online Area Calculator
The Rodosto Area Calculator lets you instantly compute the area and perimeter of a piece of land by drawing a polygon on the map. Using geodesic formulas, it delivers highly accurate results. Everything happens in your browser — your data is never sent to a server.
Features
- Polygon Drawing: Draw a free-form polygon or rectangle on the map to calculate the area.
- Multiple Units: Results are shown in m², km², hectares, donum, and acres.
- Perimeter Calculation: See the perimeter of the drawn shape in meters or kilometers.
- Manual Input: Create a polygon by entering coordinates by hand.
- Editing: Drag the drawn shape to edit it; results update instantly.
How to Use
Select the polygon or rectangle tool from the drawing controls on the left and place points on the map to complete your shape. Area and perimeter are calculated automatically. Alternatively, you can enter coordinates by hand.
Other GIS Tools
For distance between two points use the Distance Calculator, for converting between GPS formats use the GPS Format Converter, and to visualize your map data try the Map Viewer.
Frequently Asked Questions
How accurate is the online area calculator?
The tool uses geodesic (Haversine) formulas for high-precision results — accurate to within square meters for small areas, and less than 0.1% error for large areas. For legal or cadastral measurements, professional field surveys are required.
What is the difference between donum and hectare?
1 donum = 1,000 m². 1 hectare = 10,000 m², which equals 10 donum. In Turkey agricultural land is usually measured in donum, while hectares are used in international reports.
How can I enter coordinates?
In the "Manual Coordinate Input" box on the left panel you can enter coordinates in "lat,lon" format, one point per line. For example: 41.0082,28.9784. You can first convert GPS coordinates to decimal degrees with the GPS Format Converter.
Is this tool free? Is my data secure?
Yes, it is completely free. All calculations happen in your browser (client-side). Your coordinates or map data are never sent to any server.