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Converting between UTM, MTM and LAT/LONG

Canadian using a UTM map

Geographic coordinate systems enable us to spatially locate features on the Earth using specified set of two dimensional numbers. The coordinates of each feature represent the horizontal position (and sometimes vertical position when elevation is available) of it and one of the most commonly used coordinates is Geographic with values of latitude, longitude. However many different coordinate systems can be used to map the same area depending on various factors such as map extent, scale, end user etc. Therefore we often find in Geomatics that we can have data from different coordinate systems that we need to use together spatially in one reference system.

I am sure that most of us have run into times when we have features that have defined coordinates of one system that we need to use with a different one. (E.g. your map is in UTM (Universal Transverse Mercator) but you have been given GPS points in Lat/Long).

If you ever find yourself in need of quickly getting values converted from Geographic to UTM / MTM (Modified Traverse Mercator) or UTM / MTM to Geographic then here is a free online geographic coordinate convertor tool that I often use provided by Canadian Spatial Reference System

UTM Zones in Google Earth

UTM zones in Google Earth

Here is a neat little Google Earth file that has often been helpful on many of my field trips when I needed to know what UTM zone I was working in. Just open the file in Google Earth, then point and click your location to get info on that time zone. Before I found this neat little resource I was using a large JPG image that showed the zones witch I have available here.

I originaly found this file on Google but have not been able to find the original download source (have found other versions) so you here you can download my working copy here .


Every now and then I come across some little utilities that help to make things easier while working in the field and these pages are mainly my way of sharing them with others while creating a go-to place where I can easily find them when I need them. If you know of any other mapping related utilities like this then let me know and I may include it here on my site with the others.