What is a .PRJ file?
A .prj file records the coordinate system of a shapefile or raster, in Well-Known Text.
- Did you know
- The .prj file tells GIS software which map projection the data uses.
- A .prj is a sidecar for Esri’s shapefile, which deliberately splits a dataset across several files each with its own role.
- Its single line of Well-Known Text names the datum, ellipsoid, projection method and units of the data’s coordinate system.
- What Analyser reads
- Inspect geospatial and GIS files without a map: TopoJSON, OpenStreetMap XML, Esri Shapefile siblings (SHP/SHX/DBF/PRJ/CPG), world files, GML, NMEA GPS logs, IGC flight logs, MapInfo TAB/MIF, GDAL VRT, PMTiles, DTED terrain, Esri ASCII grids and SRTM .hgt - surfacing CRS/EPSG, feature/record counts, bounding boxes and elevation ranges. GRIB/NetCDF/GeoPackage/MBTiles/MrSID/ECW identified.
- Depth of analysis
- .PRJ is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .PRJ file
- Drag a .PRJ file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.