Inspect geographic data before using it on a map
If a GeoJSON file will not display as expected in a mapping tool, first check what features it contains and whether their coordinates and properties look sensible. Open the file to inspect the geometry and associated attributes before passing it to another map, GIS workflow, or web application.
Load the GeoJSON file or paste the content if the viewer supports text input.
Inspect the feature collection, geometry types, map display, and property fields. Check a few known locations against what you expect.
If a feature is missing or misplaced, inspect its coordinates and geometry in the source file before changing the data.
Check coordinates and properties together
A feature can have valid-looking properties but incorrect coordinates, or geometry that is present but not displayed at the expected location. Check that longitude and latitude are in the expected order and that the geometry type suits the feature. Empty geometry, invalid coordinate arrays, or an unexpected coordinate reference can lead to confusing results.
Viewing GeoJSON is not the same as confirming that its geographic data is authoritative or suitable for a specific map projection. Keep the source file and compare important features with a trusted reference before publishing or using the data for decisions.