Free · Local file processing · No account

Intersect Polygon Layers Online

Find shared polygon areas and retain attributes from both datasets.

Loading the local file tool…

How to use this tool

1. Choose source and overlay files, or load the working example.
2. Run the analysis and review the reported output count.
3. Download GeoJSON and inspect the result in Studio.

Limits and checks before sharing

Overlaps between different source/overlay pairs remain separate records and may overlap spatially. Boundary touches with zero area produce no polygon.
WGS 84 longitude/latitude only; reproject projected data first. Keep the original and inspect known locations in the output.
Up to 50 MB per file, 2,000 features and 20,000 vertices per layer. Polygon overlays are limited to 10,000 feature pairs. Invalid inputs fail visibly rather than being silently skipped.

If processing fails, check the file extension and source contents. Use a smaller batch if memory runs low. The original files are never overwritten. Inspect known locations and attributes before sharing a result.

Frequently asked questions

How are matching field names handled?

Source and overlay attributes are stored in separate source and overlay objects. Neither layer overwrites the other. Flatten those objects in a GIS application if your target format requires flat columns.

Are these calculations local?

Yes. Files and calculations stay in your browser. Page resources require an initial network load. Map previews can request external map tiles. No account is needed.

Continue with your result

Inspect outputs directly using the result button above. Choose a compatible next operation in the result panel to continue locally without downloading again. These related links open a fresh task. Share the downloaded file through your own channels; local files are not published to a hosted URL.