GeoJSON Validator
Paste a FeatureCollection, Feature or geometry object to catch JSON syntax errors and basic GeoJSON container mistakes without uploading the data.
By Aryan Khan, Founder & Editor · Updated October 2026
For example, a Feature whose 'coordinates' sit directly under the feature instead of inside a 'geometry' object is the classic structural slip this validator names in one paste.
How to use GeoJSON Validator
Two different ways for a file to be broken — the verdict distinguishes them:
The GeoJSON Validator checks pasted GeoJSON for JSON syntax errors and basic RFC 7946 container mistakes — wrong nesting, missing type fields, malformed positions. Paste a FeatureCollection, Feature or bare geometry and read a verdict that separates 'not JSON at all' from 'JSON, but not GeoJSON', entirely in your browser.
- 1Paste GeoJSON into the editor.
- 2Read the validation result immediately.
- 3Fix syntax or container errors and re-check.
What people use GeoJSON Validator for
1. Debugging an API response
The map renders nothing and the console is silent. Paste the response here: a trailing comma and a swapped coordinate order have very different fixes, and the GeoJSON Viewer shows whatever survives.
2. Checking hand-written fixtures
Test data written by hand fails structurally more often than syntactically. Validate before the test suite blames your code.
3. Pre-flight before conversion
Converters fail opaquely on invalid input. Validate first and the GeoJSON to CSV Converter gets the clean file it expects.
4. Learning the format's skeleton
Deliberately breaking a valid file — remove a bracket, rename a key — and reading the verdict is the fastest GeoJSON course there is.
Worked examples
A missing closing brace is a syntax error: the text is not JSON. A FeatureCollection whose members lack 'type': 'Feature' parses fine as JSON but fails as GeoJSON. The validator reports which world your file broke in.
A position needs at least two numbers, longitude first: [−73.9719, 40.7681]. A one-number 'position' or a string in the array is a structural failure the checker catches before a renderer misplaces your data by an ocean.
The RFC 7946 skeleton
The nine object types and the members each must carry.
| Type | Must contain |
|---|---|
| FeatureCollection | type + features array |
| Feature | type + geometry + properties |
| Point / MultiPoint | type + coordinates (positions) |
| LineString | type + coordinates (2+ positions) |
| Polygon | type + coordinates (linear rings, 4+ positions, closed) |
| MultiPolygon / GeometryCollection | type + member geometries |
RFC 7946 (2016) is the whole specification — GeoJSON has no versions in the wild worth fearing, and no CRS field: coordinates are WGS84 longitude/latitude by definition.
Catch common GeoJSON mistakes before loading a map
A single missing comma or malformed FeatureCollection can stop a mapping library from rendering anything. The validator parses your text locally and checks that the top-level object uses a recognized GeoJSON type, including a proper features array for FeatureCollections.
The tool intentionally avoids pretending to be a full computational-geometry validator. Self-intersections, polygon ring orientation and advanced topology need a dedicated GIS engine. For quick syntax debugging and privacy-sensitive data, the local browser check is a useful first pass.
How to interpret the result
The most common errors come from using a correct result to answer the wrong geographic question. Keep these points in mind for GeoJSON Validator:
- Validate before trusting exports from unfamiliar tools — open them in a local viewer and check feature counts, bounding boxes and a few property rows. A wrong-axis or swapped-coordinate export is far easier to catch on a map than in a spreadsheet.
- For big CSVs, fix the coordinate columns first and map a sample before mapping everything: auto-detection is good but not magical, and one swapped column renders a beautiful map of the wrong ocean.
Limits & appropriate use
File formats support different combinations of geometry, timestamps, properties and styling. Converting between them can lose information, so keep the original and inspect the output before sharing or using it.
Capabilities differ by workspace: check the accepted format and the operations actually offered on this page. Some tools process files locally but may request map tiles or other services over the network; large or specialised datasets may require dedicated GIS software.
- Cadastral/legal formats → jurisdictional land-registry exports.
- Point clouds and rasters → desktop GIS with proper spatial indexes.
- Certified tracks (evidence, insurance) → chain-of-custody originals, untouched.
Data & methodology
Local JSON parsing plus checks for recognized GeoJSON top-level types and FeatureCollection.features structure.
For source details, licences and model limitations, see Data Sources and Methodology.
Key terms worth knowing
- Bounding box
- The minimal rectangle enclosing a dataset; the instant sanity check.
- GeoJSON
- JSON geographic format; the web-mapping native dialect.
Editorial guidance: MapBench explains the method and limitations so the tool can be used as a transparent reference, not as a black-box answer. For legal boundaries, safety-critical routing, surveying, engineering, regulated decisions or official statistics, verify the result with the responsible authority or a qualified professional.
Category: Map Files. Results are intended for everyday analysis and planning unless a page explicitly states otherwise.
Method, assumptions & limits
- This tool’s method
- Local JSON parsing plus checks for recognized GeoJSON top-level types and FeatureCollection.features structure.
- Before relying on the answer
- Inspect the accepted file format and the fields reported by this specific tool. Keep a copy of the original file before converting or editing it.
- What the result cannot establish
- File geometry and recorded timestamps can be incomplete. Verify row or point counts and inspect the exported file in your target application.
Coverage: Worldwide. Search, basemap and external data requests may use third-party services; browser-based does not mean every operation is offline. Read the source and licence notes, calculation methodology and privacy policy. If a result looks inconsistent, report a correction with the inputs and mode used.
Frequently asked questions
Clear answers about the calculation, accuracy and appropriate use.
Are coordinates uploaded?
No. Validation runs locally in the browser.
Does it fully implement every RFC 7946 semantic rule?
No. It checks JSON parsing and important top-level structure. Complex ring validity and topology require a dedicated GIS geometry engine.
Is my uploaded map file sent to a server?
Where a page says browser-first or local processing, the file is handled in your browser. Check the individual tool note for any external-service dependency.
What should I do if a file will not load?
Check that the file type is supported, the structure is valid and the file is within the stated size limits. Converting to GeoJSON, GPX, KML or CSV can also help.
Will converting a file preserve every property?
Not always. Geographic formats support different geometry, style and metadata features, so inspect the output before relying on it.
Does it check the right-hand rule for polygon rings?
RFC 7946 recommends exterior rings wind counterclockwise and holes clockwise. Many parsers ignore winding; the validator concentrates on syntax and container structure, and treats winding as the recommendation it is rather than a hard failure.
Lat/lon order — can it detect swaps?
A latitude beyond ±90 inside a position is detectable and flagged. A swapped pair that stays in range (both numbers plausible) cannot be convicted by structure alone — plot the file in the viewer; geography is the witness.
What about foreign members and extensions?
Extra members are legal in GeoJSON — the spec permits foreign members. The validator does not punish a file for carrying them.
Properties: any rules?
Properties must be a JSON object or null on a Feature. An array or a bare string there is a structural error the checker names.
Can a single geometry (no Feature) validate?
Yes — bare geometry objects are complete GeoJSON. The validator accepts FeatureCollections, Features and geometries alike.
Empty coordinates arrays?
A geometry with empty coordinates is structurally tolerated by the spec's grammar but renders nothing — the validator flags emptiness as a warning worth reading.
Related tools and resources
See valid data: the GeoJSON Viewer; simplify it: the GeoJSON Simplify Helper; flatten it: the GeoJSON to CSV Converter.
More free tools
Sources, methodology & editorial trust
- ✓ Browser-first processing where supported
- ✓ External sources are documented
- ✓ No account required for public tools
- ✓ Review data sources
Calculations are documented with their assumptions, limitations and source context rather than presented as unexplained answers.
Reviewed and maintained by Aryan Khan, Founder & Editor of MapBench.
Part of our gis files hub
GeoJSON Validator sits in the gis files cluster, alongside 64 other tools that answer neighbouring questions with different methods or datasets. It also belongs to the GeoJSON tools family.
You may also need
When this answer is only part of the job, these clusters cover the next step.
Read the guide behind this tool
How to Open a GeoJSON File and Convert It to Something Else — What to do with a .geojson file you cannot open, how to check it is valid, and which conversions keep which information.