GeoJSON Validator, Converter and Analysis Tools

GeoJSON is the format most web maps speak, and most of the practical work is checking that a file is what it claims to be. Start with the GeoJSON validator for structure and coordinate-order problems, then use the feature counter or bounding box calculator to see whether the geometry and the numbers agree with what you expected.

These tools read files locally in the browser and report what they can measure: geometry types, property keys, coordinate counts, extents and areas on the sphere. They are deliberately narrow. A validator confirms structure and coordinate ranges, not topological sense — a polygon can be perfectly valid GeoJSON and still be self-intersecting or wrapped around the planet. When a conversion is involved, the tool states what it drops, because GeoJSON has no styling, no timestamps and no notion of a route.

For tracks rather than features, the GPX tools handle distance, elevation and speed. For spreadsheets and placemarks, see CSV, KML and WKT tools. To measure an area you want to draw rather than upload, the map area calculator in the area hub is the right instrument.