Outline any area on the world map and get its true size.
How this tool works
Click points on the map to outline an area; the shape closes automatically and the tool computes the true area on the sphere (not the distorted flat-map area) using the standard spherical polygon formula, along with the perimeter. Results come in square kilometers, square miles, hectares, and acres. Undo and clear buttons let you refine the outline.
What you can do with it
- Measure the true size of regions, lakes, islands, or arbitrary shapes
- Compare areas across latitudes without projection distortion misleading you
- Estimate land areas for essays, reports, and fact-checking
- Get the perimeter of the outline along with the area
Why use it
Areas measured on flat world maps can be wrong by several times at high latitudes. Computing on the sphere gives the real figure, and clicking an outline is faster than any GIS workflow for a quick measurement.
Data sources and methods
Related tools
These tools are provided for educational and informational purposes only. Results are computed from simplified public data and standard formulas, and may differ from surveyed or official values. No warranty is given as to accuracy or completeness, and the tools should not be relied on for navigation, legal, or commercial purposes.