This free online point in polygon checker lets you instantly test whether one or more coordinates fall inside or outside any polygon boundary. Upload your polygon as a GeoJSON or KML file, then add test points by clicking the map, entering coordinates manually, pasting a CSV list, or uploading a GeoJSON, KML, or GPX file. Each point is checked in real time and shown in green (inside) or red (outside) on the map.

How to Use the Point in Polygon Checker

Step 1: Load Your Polygon

Drag and drop a .geojson, .json, or .kml file onto the polygon upload area, or click to browse. You can also switch to the Paste tab and paste raw GeoJSON or KML text directly. The polygon will appear on the map highlighted in yellow. Hit Load Sample to try a rectangle around central London before using your own data.

Step 2: Add Test Points

Choose how to add the coordinates you want to test using the four tabs in the Test Points panel:

• Click Map — click anywhere on the map to drop a point. It will immediately show green if inside the polygon or red if outside.
• Manual — type a latitude and longitude and click Add. Press Enter in the longitude field to add quickly.
• Paste CSV — paste a list of coordinates one per line in lat,lng format. All points are checked and plotted at once.
• Upload File — upload a .geojson, .kml, or .gpx file containing point features. The tool will extract all points and check each one against the polygon automatically.

Step 3: Review Results

The results panel below the map shows a summary (total points, how many are inside, how many are outside) and a table listing every point with its coordinates and inside/outside status. You can remove individual points using the × button in the table.

Step 4: Download

Click Download CSV to export the full results table as a comma-separated file with columns for point number, latitude, longitude, and status (inside/outside). This can be opened directly in Excel, QGIS, or any GIS tool.

What Is a Point in Polygon Check?

A point in polygon (PIP) check is a fundamental spatial operation that determines whether a given coordinate lies inside or outside a polygon boundary. It is one of the most common operations in GIS and spatial analysis, used whenever you need to know whether a location is within a defined area.

This tool uses the Turf.js booleanPointInPolygon function, which implements the ray casting algorithm to determine containment. All calculations run entirely in your browser — no data is ever sent to a server.

Points exactly on the polygon boundary are counted as inside, which is the standard behaviour for most GIS applications.

Common Use Cases

Checking Locations Against a Service Area

Upload a service area polygon and check whether customer addresses, store locations, or delivery points fall within the boundary. The batch upload option lets you check hundreds of points from a single GeoJSON or CSV file in one step.

Validating Field Survey Data

After a field survey, confirm that GPS waypoints or track points recorded in a GPX file actually fall within the expected study area. Upload the study area boundary as a KML or GeoJSON and the GPX file as your points source.

Jurisdiction and Administrative Boundary Checks

Check whether a set of coordinates falls within a country, county, planning zone, or any other administrative boundary polygon. Download the results as a CSV to use in reporting or further analysis.

Wildlife and Environmental Studies

Determine how many animal observation records (from a GeoJSON or GPX logger) fall within a protected area or habitat polygon. The summary chip shows the inside/outside split at a glance.

Geofencing Verification

Verify whether a set of coordinates is within a geofence boundary. Upload the geofence polygon and paste or upload your coordinates to get an immediate inside/outside result for each point.

Supported File Formats

Polygon Input

• GeoJSON (.geojson, .json) — Feature, FeatureCollection, Polygon, or MultiPolygon
• KML (.kml) — Polygon placemarks including those with inner boundaries (holes)

Points Input

• Click map — any location worldwide
• Manual lat/lng entry — decimal degrees
• CSV paste — lat,lng one per line, tab or comma separated
• GeoJSON — Point and MultiPoint features
• KML — Point placemarks
• GPX — waypoints (wpt), track points (trkpt), and route points (rtept)

Frequently Asked Questions

Can I check multiple polygons at once?

Yes. If your GeoJSON or KML file contains a FeatureCollection with multiple polygon features, all of them are loaded as the boundary. A point is counted as inside if it falls within any of the polygons in the collection.

Does it support polygons with holes?

Yes. KML inner boundaries and GeoJSON polygon rings beyond the first are treated as holes. A point inside a hole is correctly reported as outside.

How many points can I check at once?

There is no hard limit. The tool processes everything in your browser. Checking thousands of points against a simple polygon is near-instant. Very complex polygons with many vertices may take a second or two for large batches.

What coordinate format do I use for manual entry?

Decimal degrees only. Latitude ranges from -90 to 90, longitude from -180 to 180. For example: latitude 51.5074, longitude -0.1278 for central London.

What does the CSV paste format look like?

One coordinate pair per line, latitude first, then longitude, separated by a comma or tab. Lines starting with # are treated as comments and ignored. Example:

51.505,-0.09
51.51,-0.10
51.49,-0.08

Can I check GPX track points against a polygon?

Yes. Switch to the Upload File tab in the Test Points panel and upload your .gpx file. The tool extracts all waypoints, track points, and route points and checks each one against the polygon. The results table and download CSV show the inside/outside status for every point.

Is my data kept private?

All processing happens locally in your browser. No coordinates, polygons, or files are uploaded to any server. Your data stays entirely on your device.