Topo50 Coordinate Conversions
Latitudes, longitudes and grid coordinates (known as northings and eastings) on the Topo50 maps are different from those used on the previous NZMS260 maps. This is because a new datum and projection were used to produce the Topo50 map series.
Datums are mathematical approximations of the earth’s shape, and projections allow these three-dimensional models to be represented in two-dimensions (ie a flat map).
The new datum and projection used for the Topo50 map series correspond to those more commonly used internationally, and in modern navigational systems, such as GPS.
| NZMS260 datum/projection | Topo50 datum/projection |
|---|---|
| New Zealand Geodetic Datum 1949 (NZGD1949) | New Zealand Geodetic Datum 2000 (NZGD2000)
For all practical purposes, this is the same as: |
| New Zealand Map Grid (NZMG) projection | New Zealand Transverse Mercator 2000 (NZTM2000) projection |
Basic conversions
If you want to convert individual coordinates between commonly used datums and projections (including those used in the Topo50 and NZMS260 maps), you can either:
- use the basic online converter or
- to make conversions offline you can download the New Zealand Map Reference Converter software.
Detailed conversions
If you want to convert coordinates between a wider range of datums, projections and height systems, and make use of format options such as bulk conversions, you can either:
- use the detailed online converter or
- to make conversions offline you can download the CONCORD software.
Note: these detailed conversion tools are recommended only if you have an understanding of coordinate and height conversions.
More information
Find out more about coordinate conversions, datums, projections and heights, and geodetic software downloads.
