I need to determine the minimum set of coordinate systems supported by all tiers of my project's stack. I have a list of EPSG codes supported by Oracle and GeoServer but I'm having trouble finding a list of systems supported by Proj4 (I intend to use the latest release of Proj4JS with OpenLayers).

The Proj4 site provides this page that "is intended to eventually contain information on all the projections supported by PROJ.4" but currently doesn't.

Does anyone know where I might find this information?

  • From the sources you can get the list of those which have been defined with EPSG-codes trac.osgeo.org/proj/export/2555/trunk/proj/nad/epsg but you can define your own with proj4 strings.
    – user30184
    Commented Oct 21, 2014 at 20:05
  • @user30184 that's quite useful thanks, I'll give it a go
    – tomfumb
    Commented Oct 21, 2014 at 20:39
  • The command line options for "proj" -lp and -le and -ld list the available coordinate systems, ellipsoids and datums. It's not possible to list every possible combination of proj coordinate systems and all parameters (obviously) but those three lists give you a huge range of components to define what you need.
    – mdsumner
    Commented Oct 21, 2014 at 21:22
  • I came here when googling for a 'definitive' list of proj4 definitions for coordinate systems with EPSG codes and want to give a word of warning. I have some data using the (deprecated) CRS EPSG:2400 (the data is what it is..), and using both proj4js and mproj, when converting to WGS84, kept getting results that were translated away from where they should be. It turns out that I was using the proj4 definition given by <spatialreference.org>: +proj=tmerc +lat_0=0 +lon_0=15.80827777777778 +k=1 +x_0=1500000 +y_0=0 +ellps=bessel +units=m +no_defs As per @user30184's suggestion I checked
    – user80470
    Commented Aug 9, 2016 at 13:49

1 Answer 1


Please note that Proj.4 and proj4js are not identical.

If you download the latest version of proj4js, you find the defined projections in the lib/projections folder.

Regarding EPSG codes, proj4js only has a few definitions, look into lib/global.js or see http://proj4js.org/ But it is possible to build all other definitions yourself if you take the proj4 definition string from the original, from QGIS or from http://spatialreference.org.

  • wait, I'm still confused - if proj4js only has a few EPSG definitions how is it that, once included, OpenLayers lets me say new OpenLayers.Projection('EPSG:2269') for example? I don't understand how these EPSG codes are associated with the relevant proj transform parameters. All I need to know is which EPSG strings will be understood out of the box
    – tomfumb
    Commented Oct 23, 2014 at 20:39
  • OK perhaps I misunderstood how OpenLayers was handling my input string... I will have to study this problem a little more.
    – tomfumb
    Commented Oct 23, 2014 at 20:46
  • I remember that openlayers will look up online under spatialreference.org. But that source did not get any maintenance recently.
    – AndreJ
    Commented Oct 24, 2014 at 3:40

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