Enter GPS coordinates (one “latitude, longitude” pair per line, in order around the boundary)
Paste coordinates from a GPS device, a field survey, or another map tool. At least 3 points are needed.
| Measurement | Value |
|---|---|
| Area | — |
| Perimeter | — |
This tool calculates area using your points’ real GPS coordinates and the curvature of the Earth, so it works at any scale — a backyard or a large field. Satellite imagery and GPS positioning are not survey-grade: for legal boundaries, financing, or construction, confirm measurements with a licensed surveyor.
If you can see a piece of land on a map but nobody has ever measured it, you are stuck. A house lot, a farm field, a wooded parcel, or a plot you are thinking of buying might have no recorded square footage anywhere you can find.
This tool solves that by letting you mark the boundary directly on a satellite or street map -- or by pasting in GPS coordinates you already have -- and it calculates the area and perimeter for you. It covers map area measurement, GPS-coordinate area calculation, satellite land measurement, and address-based location search, all in one tool, so you do not need a separate calculator for each way of finding your boundary.
What This Map Area Calculator Does
You start by finding the location: search an address or place name, type in coordinates, or use your device's GPS to center the map on where you are standing. Then you click points around the edge of the area you want to measure -- a lot line, a fence, a field edge, a building outline -- and the tool closes the shape and reports its area and perimeter.
If you already have a list of GPS coordinates (from a handheld GPS unit, a drone survey export, or another mapping tool), you can paste them in directly instead of clicking, and the same calculation runs on those points.
Satellite View vs Street View
The map defaults to satellite imagery, which is usually the more useful view for tracing a real boundary -- you can see the actual tree lines, fences, rooflines, and paved edges. A street-map layer is also available, which can make it easier to line up a boundary against a plotted parcel line, road, or address point when the satellite photo is unclear or outdated.
How to Calculate Area from a Map
The process has three stages: get to the right place, mark the boundary, and read the result.
1) Find Your Location
There are three ways to get to the area you want to measure.
Search by address or place name
Type an address, a town, or a landmark into the search box and the map will center on it. This uses an open map-search service, so results depend on how well the location is indexed -- a full street address usually works better than a vague description.
Enter coordinates directly
If you already know the latitude and longitude of the area (for example, from a property deed or a GPS device), type them into the same search box as "latitude, longitude" -- for example, 40.785091, -73.968285 -- and the map will jump straight there.
Use your current GPS location
On a phone or a laptop with location enabled, the "Use my location" button centers the map on where you are standing right now, using your browser's GPS or network location. This is useful for measuring a field or lot while you are on site.
2) Mark the Boundary
Once you can see the area clearly, click each corner of the boundary in order, working around the shape in one direction. Each click drops a numbered point and connects it to the last one. Zoom in for sharper corners and zoom out to check the overall shape as you go. If you place a point in the wrong spot, use "Undo point" to remove the most recent one without starting over.
3) Close the Shape and Read the Results
Once every corner is marked, click "Close shape." The tool connects the last point back to the first, fills in the shape, and calculates the area and perimeter immediately below the map. You can switch the area unit at any time -- square feet, square meters, acres, hectares, square kilometers, or square miles -- without re-drawing anything.
Measuring Land Using GPS Coordinates Instead of Clicking
Clicking on a map is not always the most accurate option, especially for a boundary you have already surveyed or recorded some other way. The "Enter GPS coordinates instead" option lets you skip the map entirely.
When to Use Coordinate Entry
Coordinate entry is the better choice when you already have a list of points from a handheld GPS unit, a drone or aerial survey, a deed description that has been converted to coordinates, or another mapping tool's export. Typing in known coordinates avoids the small placement error that comes from clicking on a photo at a given zoom level.
Coordinate Format and Order
Enter one point per line, as "latitude, longitude" -- for example:
40.785091, -73.968285
40.800275, -73.958352
40.796485, -73.949232
List the points in order as you would walk the boundary, either clockwise or counter-clockwise. You need at least three points. Once you click "Plot these points," the tool draws the shape on the map so you can visually confirm it looks right, and calculates area and perimeter the same way as a shape you clicked by hand.
How the Area Is Calculated
Once a boundary is defined by a set of latitude/longitude points, the calculator works out the enclosed area and the perimeter.
Geodesic Area, Not a Flat Formula
A simple shoelace-style area formula (the one used for flat, drawn shapes measured in a fixed unit like meters) is not accurate for GPS coordinates, because a degree of longitude covers less real-world distance the further you are from the equator, while a degree of latitude stays roughly constant. This calculator accounts for that by computing area on a sphere the size of the Earth, rather than treating latitude and longitude as if they were a flat grid. That is why the same shape "size" in degrees gives a different real-world area depending on where on the globe it is drawn.
Where:
- Each boundary point contributes based on its longitude difference from the next point and the sine of both points' latitudes
- The sum is scaled by the Earth's radius squared to convert it from an angular quantity into a real ground area
For a small residential lot or field, this produces effectively the same result as a flat calculation would -- the correction only becomes significant at larger scales or higher latitudes -- but using the geodesic method means the same calculator stays accurate whether you are measuring a suburban yard or a large rural parcel.
Perimeter Calculation
Perimeter = sum of the great-circle distance between each pair of consecutive boundary points, including the closing segment back to the first point.
Great-circle distance is the shortest path between two GPS coordinates along the Earth's curved surface, which is the standard way to measure real-world distance between two latitude/longitude points.
Worked Examples
Example 1: A House Lot by Satellite
Suppose you search your own address, switch to satellite view, and click the four corners of your backyard as you see them in the photo, then close the shape.
The calculator might report an area of 6,200 square feet and a perimeter of 320 feet. Switching the unit dropdown to acres shows the same area as roughly 0.14 acres -- useful when comparing to a property listing that quotes lot size in acres.
Example 2: A Farm Field from GPS Coordinates
Suppose you walked the edge of a field with a handheld GPS unit and recorded six coordinate pairs. Pasting those six lines into the coordinate box and clicking "Plot these points" draws the field boundary and might report an area of 8.7 hectares, or about 21.5 acres, with a perimeter of 1,340 meters.
Example 3: Finding a Location by Address First
If you do not know the exact coordinates of a parcel, search a nearby address or town first to get the map centered in roughly the right place, then zoom in using the map's normal zoom controls until you can clearly see the boundary you want to trace, and begin clicking points from there.
Accuracy of Map and GPS Area Measurements
A map- or GPS-based area is an estimate, not a legal survey. Two things limit how precise it can be.
Sources of Error
Satellite imagery alignment
Satellite and aerial photos are stitched together from images taken at different times and angles, so a boundary that looks perfectly sharp on screen can still be offset from its true position by a small amount, and tall objects near a boundary (trees, buildings) can appear to lean due to the camera angle.
Consumer GPS accuracy
A phone's or handheld GPS unit's reported position is typically accurate to within a few meters under normal conditions, and can be less accurate near tall buildings, dense tree cover, or in poor weather. That margin of error applies to every point you record, which affects the resulting area and perimeter.
When to Use a Licensed Surveyor Instead
For anything where the exact boundary matters legally or financially -- a property line dispute, a land purchase, a construction setback, or a subdivision -- use a licensed land surveyor's measurement, not this or any other map-based tool. This calculator is meant for planning, estimating, and getting a quick, practical sense of an area's size.
Choosing Units: Acres, Hectares, Square Feet, and More
The unit dropdown converts the same measured area between square feet, square meters, acres, hectares, square kilometers, and square miles instantly, without needing to re-measure anything. Acres and hectares are the most common units for land and field size, square feet and square meters suit house lots and yards, and square miles or square kilometers suit very large areas.
Map Area Calculator vs Other Tools on This Site
Each area tool on this site fits a different starting point:
- Map/GPS tool (this page): Use when you want to find a real-world location on a live map or already have GPS coordinates
- Draw Area Calculator: Use when you have a sketch or rough layout and want to draw it to a scale you set yourself, with no map involved
- Image Trace Area Calculator: Use when you have an uploaded photo or floor plan and want to trace its outline directly
Choosing the one that matches what you already have -- a real location, a sketch, or a photo -- gets you to an answer faster.
Frequently Asked Questions
1. How do I calculate land area from a map?
Search your location or use your GPS to get to the right spot on the map, click each corner of the boundary in order, then click "Close shape." The area and perimeter are calculated immediately.
2. Can I calculate area from GPS coordinates instead of clicking on a map?
Yes. Click "Enter GPS coordinates instead," paste in your latitude/longitude points (one pair per line, in boundary order), and click "Plot these points."
3. How accurate is a satellite map area calculator?
It is accurate enough for planning and estimating, but it is limited by satellite imagery alignment and GPS positioning error, both of which are typically a few meters at most. For legal or financial decisions, use a licensed surveyor's measurement instead.
4. What units can I use for the area?
Square feet, square meters, acres, hectares, square kilometers, and square miles. Switch between them at any time using the dropdown above the results -- the underlying measurement does not change, only how it is displayed.
5. Does this tool work for very large areas, like an entire farm?
Yes. The area is calculated using the real curvature of the Earth rather than a flat approximation, so it stays accurate whether you are measuring a small yard or a large field.
6. Can I export my measurement?
Yes. "Copy coordinates" copies your boundary points to the clipboard, and "Export CSV" downloads a file with your coordinates plus the calculated area (in several units) and perimeter.
7. Why does the tool ask for satellite view instead of just using street view?
Satellite imagery shows the actual physical features on the ground -- fence lines, tree cover, rooflines, paved areas -- which is usually what you are trying to trace. Street view is still available and can help when you want to line a boundary up against a road or an address point.