Free Online WKT & GeoJSON Viewer

Spatial-Sandbox is a fast, browser-based geospatial utility for inspecting, visualizing, converting, and debugging Well-Known Text (WKT) and GeoJSON geometries on interactive Leaflet maps. Completely free, no login, and runs entirely on your device.

Quick Tools

WKT Viewer β†’

Paste or load any Well-Known Text geometry (Point, LineString, Polygon, Multi-geometries) and render on OSM / Satellite maps.

GeoJSON Viewer β†’

Visualize GeoJSON geometries, Features, and FeatureCollections with automatic coordinate detection and layer styling.

WKT Validator β†’

Validate WKT syntax, inspect coordinate ordering, verify ring closure, and troubleshoot PostGIS spatial queries.

Supported Geometry Formats & Types

Spatial-Sandbox supports all standard OGC simple features in both WKT and GeoJSON formats, with automatic type detection:

POINT MULTIPOINT LINESTRING MULTILINESTRING POLYGON MULTIPOLYGON GEOMETRYCOLLECTION

Quick Examples β€” Try in Map

Copy any of the sample geometries below or click Load in Map to render them immediately on the interactive canvas:

POINT(2.2945 48.8584)
LINESTRING(-122.4786 37.8100, -122.4783 37.8199, -122.4780 37.8300)
POLYGON((-73.9731 40.7644, -73.9579 40.7972, -73.9818 40.8005, -73.9819 40.7681, -73.9731 40.7644))
{"type":"Feature","geometry":{"type":"Point","coordinates":[-0.1246,51.5007]},"properties":{"name":"Big Ben, London"}}

🌐 CRS Reprojection

Works with standard WGS84 (EPSG:4326), Web Mercator (EPSG:3857), British National Grid (EPSG:27700), UTM zones, and any custom projection via Proj4js.

πŸ’Ύ Multi-Format Export

Export any geometry or entire workspaces to WKT, GeoJSON, PostGIS WKB (Well-Known Binary), EWKB hex strings with SRID, or Bounding Box coordinates.

✏️ On-Map Drawing Tools

Draw points, polylines, polygons, and bounding boxes directly on the map with real-time length and area measurements powered by Turf.js.

πŸ”’ 100% Client-Side Privacy

Your geometry data never leaves your browser. All parsing, validation, reprojection, and rendering occur locally on your machine.