Free tool
Lat/long to MGA converter and zone finder
Convert between latitude and longitude and MGA eastings and northings. Finds the zone from the longitude. Shows grid convergence and point scale factor.
Enter latitude and longitude as decimal degrees, or as degrees minutes seconds such as -37 48 49.0. You can also end a value with N, S, E or W. The same formulas apply to GDA2020 with MGA2020 and GDA94 with MGA94: use the datum your coordinates are in.
Method and limits
- Uses the Transverse Mercator projection on the GRS80 ellipsoid: central scale factor 0.9996, false easting 500,000 m, false northing 10,000,000 m, 6 degree zones with central meridian 6 x zone - 183 degrees east. Zone = floor((longitude + 180) / 6) + 1.
- Checked against PROJ on 3,000 random points across zones 49 to 56, including points up to 3.6 degrees from the central meridian: eastings and northings agree to within 0.00000001 m. The round trip back to lat/long was checked as well.
- This converts between lat/long and grid in the same datum. It does not convert between GDA94 and GDA2020: use the GDA94 to GDA2020 converter for that.
- Outside zones 49 to 56, or beyond the stated limits, the tool says so instead of guessing.
- This tool is a convenience, not a survey deliverable. Check results against your own work, and use certified methods for anything you sign off. Provided as is, in line with the terms. Nothing you enter is sent anywhere.