Area Calculator
Draw a boundary on the map, or import a KML, KMZ or GeoJSON file, and get its geodesic area in hectares, acres, m² and more, plus the perimeter, centre and bounding box.
- Runs in your browser
- No sign-up
- Free
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How this calculator measures an area
The area is geodesic: it is computed on the surface of the WGS 84 sphere rather than on a flat projection, so it stays correct for a one-hectare field and for a region hundreds of kilometres across. A planar calculation in Web Mercator, which is what many quick scripts use, overstates an area at 50° latitude by more than half.
Three ways to get your boundary in
- Draw it: press Draw area, click each corner on the map, then double-click to close the shape. Drag the white handles to adjust, or Alt-click one to delete that corner.
- Import a file: KML and KMZ from Google Earth, or GeoJSON from QGIS, ArcGIS and most web maps. The first polygon in the file is used.
- Paste coordinates: one point per line, latitude first, in decimal degrees (
28.6139, 77.2090) or DMS (28°36'50"N, 77°12'32"E).
Which unit to use
- Square metres (m²): SI unit, best for small plots and building footprints.
- Hectares (ha): 1 ha = 10,000 m². The working unit for farms and survey sites.
- Acres: 1 acre ≈ 4,047 m². Common in US and UK land records.
- Square kilometres (km²): for corridors, districts and whole-region projects.
What people use it for
- Drone mapping: turn a site boundary into a flight count, battery count and image count.
- Land surveying: check a parcel area against the title document before going out.
- Agriculture: field sizes for input planning, spraying and yield estimates.
- Construction: site extents, earthwork boundaries and stockpile footprints.
Area Unit Conversions
| Unit | Square Meters | Acres | Sq Km | Sq Miles |
|---|---|---|---|---|
| 1 Hectare (ha) | 10,000 | 2.471 | 0.01 | 0.00386 |
| 1 Acre | 4,047 | 1 | 0.00405 | 0.00156 |
| 1 Square Kilometer | 1,000,000 | 247.1 | 1 | 0.386 |
| 1 Square Mile | 2,590,000 | 640 | 2.59 | 1 |
Drone Coverage by Platform
| Drone Type | Coverage/Flight | Flight Time | Notes |
|---|---|---|---|
| DJI Mini Series | 15-25 ha | 25-30 min | Consumer, limited payload |
| DJI Mavic 3 / Air 2S | 30-50 ha | 35-45 min | Prosumer mapping |
| DJI Phantom 4 RTK | 40-60 ha | 25-30 min | Professional, RTK accuracy |
| DJI Matrice 300 RTK | 50-80 ha | 40-55 min | Enterprise, multi-payload |
| senseFly eBee X | 200-500 ha | 60-90 min | Fixed-wing, large area |
Frequently Asked Questions About Area Calculation
Upload your KML file to our Area Calculator. The tool automatically parses polygon coordinates and calculates geodesic area in multiple units (hectares, acres, square kilometers). Works with KML files from Google Earth, QGIS, ArcGIS, and other GIS software.
A typical mapping drone (DJI Mavic 3, Phantom 4) covers 30-50 hectares per battery at 120m altitude with 75% overlap. Actual coverage depends on GSD requirements, overlap settings, wind conditions, and flight speed. Fixed-wing drones can cover 200+ hectares per flight.
Geodesic calculation accounts for Earth's curvature, giving accurate results for any polygon size. Planar calculation treats the surface as flat, which causes significant errors for large areas. Our calculator uses geodesic methods for professional accuracy.
1 hectare = 2.471 acres = 10,000 m² = 0.01 km². Our calculator automatically displays area in multiple units. For reference: a typical city block is about 1-2 hectares, a football field is about 0.5 hectares.
Yes. Upload a .geojson or .json file alongside KML and KMZ. One polygon is measured at a time: if the file holds several, the first is used and the tool says so on import. Interior holes are not subtracted, so the figure is the outer boundary. The paste box takes typed coordinates, one lat, lng per line, rather than raw GeoJSON.