GPS, UTM, MGRS, USNG: what’s it all about?

This stuff should be finished by now, but it turned out to be much more difficult than I imagined. However, things are at last progressing. You will now find:

• UTM, MGRS and the USNG: what are they, and how do you convert between them?

  Written for world-wide users of GPS equipment who are interested in understanding more about the numbers generated by their equipment. Includes links to source material

• Tables of MGRS Grid Letters: see box above
• Your own UTM to MGRS (and USNG) convertor: a simple HTML/JavaScript page that you can use off-line. Originally written to illustrate how conversion between MGRS and UTM can be done using straightforward techniques, but useful in its own right
  • Convertor program documentation: a "How it's done" for the masochists among you, and those who would like to write their own convertor

Still to come...

• Introduction to GPS: What is it and how to use it
• The Datum: why are my references 500m off?
• The Ellipsoid
• Why use MGRS rather than latitude and longitude? What are the snags with both?

Revised 2003-09-21

Uprated to xhtml 2005-08-16