How do I find out (calculate somehow) the central meridian for a UTM zone for which I know the zone number?


2 Answers 2


The central meridian of a 6 degree wide UTM zone will be given by:

 (zone_number * 6 - 180) - 3 
  • Is it something that reliably works for every zone number? I'm asking 'cause there's a script to convert lat/lng to zone number and it is said to have weird exceptions.
    – jayarjo
    Dec 14, 2021 at 15:04
  • should work for all of the 6 degree wide ones which is all anyone except NATO use.
    – Ian Turton
    Dec 14, 2021 at 15:09
  • oh... NATO countries you mean? or you mean they have their own twisted version of UTM?
    – jayarjo
    Dec 14, 2021 at 18:37
  • 1
    No, they are the only people who use the wierd ones north of Norway
    – Ian Turton
    Dec 14, 2021 at 19:07

EPSG lists the Central Meridian in its Coordinate System Definitions: https://epsg.io/ Or you can see all the UTM Grid Zones of the World: http://www.dmap.co.uk/utmworld.htm

  • So I cannot do without external information? I was looking to have it local somehow in just one utility, 'cause in theory all the information should already be included in zone number and coordinates :/
    – jayarjo
    Dec 14, 2021 at 6:18
  • I was looking for an algorithm basically to use in my conversions script.
    – jayarjo
    Dec 14, 2021 at 6:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.