Free · Local file processing · No account

Add Area & Length Fields Online

Add geodesic area and line length to your dataset without overwriting existing attributes.

Loading the local file tool…

How to use this tool

1. Choose a dataset 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

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

What is measured?

Polygon and MultiPolygon area uses the WGS 84 spherical area model. LineString and MultiLineString length is geodesic. Points and GeometryCollections remain in the output without measurement fields.

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.

Edit Feature Attributes Online

Edit attribute values, add or rename fields, and remove unwanted columns before sharing a GIS dataset.

Split Dataset by Attribute Online

Turn a mixed dataset into separate files for each attribute value.

Convert GeoJSON output to KML for Google Earth Check GeoJSON structure before publishing