About KunYu

KunYu was created by a GIS and AI engineer who builds geospatial applications every day. The frustration of constantly switching between epsg.io, geojson.io, mapshaper, and custom coordinate conversion scripts was the direct motivation — there had to be a better way.

This hands-on experience in production GIS workflows, including working with Chinese coordinate systems (GCJ-02 and BD-09) that most international tools don't support, shapes every feature and tool in KunYu.

GIS professionals and developers often need to juggle between multiple websites and scripts for different tasks: looking up EPSG codes on one site, editing GeoJSON on another, converting formats somewhere else, and running coordinate transformations in yet another tool. Each context switch breaks focus and wastes time.

KunYu consolidates coordinate conversion, EPSG search, GeoJSON editing, format conversion, spatial analysis, and 12 more tools into a single, fast, and free platform — so you can stay in flow and get work done.

KunYu is powered by well-established open-source geospatial libraries, the same ones used by professional desktop GIS software:

• Proj4js — the JavaScript port of the PROJ library, providing coordinate transformation for 6,000+ coordinate reference systems from the EPSG Registry
• Turf.js — advanced geospatial analysis including buffering, simplification, boolean operations, and measurement
• MapLibre GL JS — high-performance, open-source map rendering with WebGL
• Format I/O — specialized parsers and writers for Shapefile, KML, GPX, CSV, GeoJSON, WKT, and WKB

KunYu is built entirely on open standards and specifications: RFC 7946 for GeoJSON, the EPSG Geodetic Parameter Registry maintained by IOGP, OGC standards for WKT and WKB, and open data formats including KML (OGC), GPX, Shapefile, and CSV. There is no vendor lock-in — your data stays in standard, interoperable formats compatible with QGIS, ArcGIS, Google Earth, and every major GIS platform.