GeoJSON Viewer & Validator
Visualize, inspect, validate, and edit GeoJSON files on a responsive map. View attribute tables, feature counts, and geometry properties.
The GeoJSON Viewer validates and renders RFC 7946 GeoJSON files, FeatureCollections, and geometry objects directly on an interactive map. It provides syntax validation, feature property tables, bounding box calculation, topology inspection, and one-click conversion to KML, GPX, or CSV.
GeoJSON Code Editor
Vector Map Rendering
GeoJSON Viewer Technical Specifications & Standards
WGS84 (EPSG:4326)
Standard global ellipsoidal coordinate reference system
IETF Geodesics
Full float64 precision
GeoJSON · KML · CSV · SVG
Compatible with QGIS, ArcGIS, Google Earth & CAD
100% Client-Side
Calculations run in-browser. Zero coordinate logging.
How to Use the GeoJSON Viewer & Validator
Follow this step-by-step procedure to execute precise spatial measurements and export results.
- 1Paste or upload GeoJSON: Paste raw JSON text into the editor or upload a .geojson / .json file.
- 2Automatic RFC 7946 validation: The parser validates JSON syntax, geometry types (Point, LineString, Polygon, MultiPolygon), and coordinate bounds.
- 3Inspect feature properties: Click any feature on the map or in the data table to review its attributes and properties.
- 4Export or convert: Download validated GeoJSON, or convert to KML (Google Earth), GPX, or CSV.
Geodesic Precision vs. Competitor Mapping Approaches
Most legacy mapping utilities (such as CalcMaps and FreeMapTools) rely on planar Web Mercator projections or spherical approximations, causing significant mathematical distortion at higher latitudes. GeoMap Suite computes exact ellipsoidal geodesics on the WGS84 reference ellipsoid.
| Calculation Model | Mathematical Basis | Distortion on WGS84 | Standard Tools | Practical Application |
|---|---|---|---|---|
| Planar (Web Mercator) | Cartesian dx² + dy² | 10% to 200%+ error | CalcMaps / Simple map tools | Distorts drastically away from equator. Inaccurate for true distance. |
| Spherical Great-Circle | Haversine (R = 6,371 km) | Up to 0.5% (~5 km/1,000 km) | Basic Google Maps wrappers | Ignores Earth's polar flattening. Reasonable for rough estimates. |
| GeoMap Suite Ellipsoidal | Karney Direct/Inverse WGS84 | < 15 nanometers (<0.0001%) | GeoMap Suite | Geodetic surveying, maritime, flight paths & legal boundary analysis. |
Worked Example: Inspecting a City Boundary FeatureCollection
A web developer validates a GeoJSON file containing municipal zoning districts before deploying to a web app.
Input Parameters
- File Type
- Municipal_Boundaries.geojson (RFC 7946)
- Size
- 1.2 MB / 85 Features
Computed Outputs
- Validation Status
- Valid RFC 7946 GeoJSON
- Feature Count
- 85 Polygons
- Bounding Box
- [-122.52, 37.70, -122.35, 37.83]
Step-by-Step Mathematical Process
- Parse JSON syntax and verify root type: "FeatureCollection".
- Verify coordinate winding order: Exterior rings are counter-clockwise per RFC 7946.
- Render vector layer with interactive hover tooltips for properties (e.g. zone_id, acreage).
- Calculate total bounding box: [-122.52, 37.70, -122.35, 37.83].
Understanding Your Results & Practical Interpretation
The GeoJSON Coordinate Order Standard ([Longitude, Latitude])
RFC 7946 strictly requires coordinates in [Longitude (X), Latitude (Y)] order. Entering latitude first is the most common error in GeoJSON development. GeoMap Suite automatically validates coordinate order and detects out-of-bounds latitude values (>90°).
Practical Applications & Real-World Use Cases
Web GIS Development & API Payload Testing
Test, inspect, and debug GeoJSON responses from REST APIs, Mapbox, and Leaflet backends.
Mathematical Methodology & Geodetic Accuracy
IETF RFC 7946 GeoJSON Specification Validator
Validates JSON structure against the official IETF RFC 7946 standard, verifying coordinate dimensions, ring closure, and property schemas.
Validate(JSON) → {isValid, errors, featureCount, bbox, geometryTypes}Limitations & Boundary Conditions
- •Non-WGS84 CRS coordinate reference systems are flagged with a warning per RFC 7946.
Authoritative Reference Standards
Troubleshooting & Geographic Edge Cases
What does "LinearRing must have 4 or more coordinates" mean?
In GeoJSON, polygon outer rings must have at least 4 coordinate pairs, and the first coordinate must match the last coordinate to close the ring.
Frequently Asked Questions
A Feature represents a single spatial object with a specific geometry (e.g., Point or Polygon) and a properties dictionary. A FeatureCollection is an enclosing array containing multiple Feature objects.