How to Measure Distance, Area, and Radius on a Map

MeasureMaps is a free tool for measuring distance, land area, acreage, radius, perimeter, and elevation on an interactive map. Search any address, drop points, and get accurate Great-circle measurements, then export to GeoJSON, KML, CSV, or JSON for use in GIS software.

Measurement tools

Open the map and start measuring →

Frequently Asked Questions

What can I measure?

Measure distances for simple lines and complex polylines. Area measurement lets you outline parcels, lots, or fields with real-world accuracy. Circle measurement allows you to measure circular areas and radius distances — perfect for coverage zones, service areas, or circular boundaries.

How accurate is it?

Lines are drawn as Great-circle arcs — the shortest path between two points on Earth. Bearings and distances follow the same math, so results stay realistic even across long spans. The arrows you see mark the true midpoint of the Great-circle distance, not the optical middle of the projection (a difference you will notice more in higher latitudes).

What is Great-circle distance?

It is the path you would fly if you hugged the Earth's curvature — the geodesic between two points. Using it avoids the distortions that flat map projections introduce, keeping your measurements aligned with reality.

How do I finish a line?

Double-click, single-click the last point (in orange), or press Escape.

Can I move points?

Yes. Click and drag any point. Mobile support depends on the browser — on some touch setups (such as Chrome Mobile) dragging is not guaranteed to work perfectly.

How do I extend or edit shapes?

You can extend and edit a shape after drawing it:

  • Hold Ctrl/Cmd and click an endpoint to continue a line.
  • Hold Ctrl/Cmd and click an arrow along the line to add a new point.
  • Hold Shift and click a point to delete it.

How is area calculated?

Area calculations use spherical geometry to account for the Earth's curvature. For polygons, we compute the area on the surface of a sphere, which gives accurate results even for large regions. The calculation considers the Great-circle segments between vertices, ensuring measurements reflect real-world surface area rather than flat map projections.

Why do distance measurements differ from straight-line calculations?

Straight-line calculations on a flat map ignore the Earth's curvature. Our measurements use Great-circle distance, which follows the shortest path along the planet's surface. This is especially noticeable over long distances or at high latitudes, where map projections distort distances significantly.

Can I measure across the International Date Line or poles?

Yes. The Great-circle calculation handles edge cases like crossing the 180° meridian (International Date Line) and measurements near the poles correctly. The system automatically accounts for these geographic boundaries to provide accurate results.

How precise are the measurements?

Precision depends on several factors: the accuracy of the map imagery, how precisely you place points, and the distance being measured. For typical use cases, measurements are accurate to within a few meters for distances under 100km. For very long distances (thousands of kilometers), the Great-circle method ensures the calculation itself is mathematically correct, though placement precision becomes more critical.

Do measurements account for elevation?

Elevation data is displayed at each measurement point using the Open-Meteo Elevation API. For distance measurements, you'll see the elevation and elevation change at each point. For area measurements, the elevation range (min–max) is shown. For circle measurements, the center elevation is displayed. Note that distance and area calculations are still based on a spherical model at sea level — the elevation data is informational and included in exports (GeoJSON, KML, CSV).

Can I export or save my measurements?

Yes! You can export all your measurements in multiple formats. Click the "Export" button in the menu bar to download your measurements as GeoJSON (for GIS software), KML (for Google Earth), CSV (for spreadsheets), or JSON (raw data format). All exported files include detailed measurement data including coordinates, distances, areas, perimeters, and formatted values. Exported files are named with "measuremaps.com" prefix for easy identification.

What units are available for distance measurements?

Distance measurements support three unit systems: metric (meters and kilometers), imperial (feet and land miles), and nautical (nautical miles). Use the unit control button on the distance measurement tool to switch between units. Nautical miles are particularly useful for maritime and aviation applications, as they are based on the Earth's latitude and provide consistent distance measurements regardless of location. Area measurements use square meters/kilometers for metric or square feet/miles for imperial units.

How do I measure a circle or radius?

Use the circle measurement tool (circle icon) in the top-left corner of the map. Click once to set the center point, then move your mouse to adjust the radius. You'll see a preview circle with the current radius displayed. Click again to finish and view both the radius distance and the total area of the circle. This is useful for measuring coverage areas, service zones, or any circular boundaries.

Can I measure both radius and area with the circle tool?

Yes! When you finish drawing a circle, the tool displays both measurements: the radius (distance from center to edge) and the total area within the circle. The radius is shown in meters/kilometers (metric) or feet/miles (imperial), and the area is shown in square meters/kilometers or square feet/miles, depending on your unit preference.

Is MeasureMaps free to use?

Yes. MeasureMaps is a completely free online map measurement tool. You can measure unlimited distances, areas, and radius circles, and export your results to GeoJSON, KML, CSV, or JSON at no cost — no subscription, no watermark, and no usage limits.

Do I need to create an account or sign up?

No account or sign-up is required. Just open the map and start measuring. If you want to save a measurement and get a shareable link, you can do that instantly without registering.

How do I measure the distance between two points on a map?

Select the distance (ruler) tool, click the first point on the map, then click the second point. MeasureMaps instantly shows the distance between the two points using accurate Great-circle calculations. Keep clicking to add more points and measure a multi-segment path, and read the running total as you go.

How do I measure land area or acreage on a map?

Use the area tool to outline a parcel, lot, or field by clicking each corner, then close the shape to see its total area. Areas are shown in square meters and square kilometers (metric) or square feet and square miles (imperial), and exports also include hectares. To read the value in acres: 1 acre = 4,047 m² = 0.405 hectares = 43,560 sq ft.

How do I draw a radius around a point on a map?

Select the circle tool, click once to place the center point, then move the mouse out to the distance you want and click again. The circle shows the radius (the distance from the center to the edge) and the total area covered — ideal for drawing a service area, coverage zone, or "how far can I reach" radius around any location.

How do I measure the perimeter of a property or field?

Outline the property with the area tool. Along with the enclosed area, MeasureMaps calculates the perimeter — the total length around the boundary. The perimeter is included in every export (GeoJSON, KML, CSV, and JSON) so you can use it in reports or GIS software.

Does MeasureMaps work on mobile phones and tablets?

Yes. MeasureMaps runs in any modern mobile browser, so you can measure distance, area, and radius on your phone or tablet without installing an app. Note that dragging existing points to reposition them may not work reliably on some touch browsers (such as Chrome Mobile).

Can I share my measurements with a link?

Yes. Use the Save option to store your measurements and generate a short, shareable URL. Anyone with the link can open the exact same measurements on the map — useful for sending a plot, route, or coverage area to a colleague or client.

How is this different from measuring distance on Google Maps?

Google Maps offers basic point-to-point distance. MeasureMaps adds polygon area and perimeter, circle radius and coverage area, elevation data, three unit systems (metric, imperial, and nautical), Great-circle accuracy, shareable links, and one-click export to GeoJSON, KML, CSV, and JSON for use in GIS software like QGIS and ArcGIS.

What map data does MeasureMaps use?

The map is powered by OpenStreetMap, an open, community-maintained map of the world. Address and place search uses OpenStreetMap-based geocoding, so you can find any location worldwide before you measure.

How do I convert square meters to acres, hectares, or square feet?

Use these conversions for area measurements: 1 hectare = 10,000 m² = 2.471 acres; 1 acre = 4,046.86 m² = 0.4047 hectares = 43,560 sq ft; 1 square kilometer = 100 hectares = 247.1 acres; 1 square mile = 640 acres = 2.59 km². Every MeasureMaps export includes the raw value in square meters so you can convert to any unit you need.

Back to the MeasureMaps tool