About EPSG Transform

EPSG Transform is a free online tool that lets you convert coordinates between any pair of EPSG-registered Coordinate Reference Systems (CRSs). It supports all 7,000+ active EPSG codes, including geographic systems (WGS 84, NAD83, ETRS89), Web Mercator, UTM zones, national grids, and local/regional projections.

How it works

All transformations run entirely in your browser using proj4js, a JavaScript port of the PROJ library. CRS definitions come from the same EPSG Geodetic Parameter Dataset used by every major GIS package. Your coordinates never leave your device.

Accuracy & caveats

Projection-only conversions (e.g. WGS 84 ↔ Web Mercator) are accurate to centimetres. Datum shifts using Helmert seven-parameter transformations are accurate to a few metres. High-precision grid-based datum shifts (NTv2, NADCON) require external grid files and are not currently performed in-browser.

Data version

All CRS definitions and transformation parameters on this site are built from EPSG Geodetic Parameter Dataset v12.029 (released 2025-10-02) as distributed with PROJ 9.8.1. We rebuild the site when new dataset versions are published.

About EPSG Transform

How it works

Accuracy & caveats

Data version

Attribution