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Navigational gear worldwide

I'm not that well travelled (never been outside of Europe!) but at some point I'd love to head elsewhere to perhaps hike somewhere a bit more exotic.

I've heard (quite a bit) that most compasses only come calibrated for one hemisphere - how much "out" is a compass in the wrong part of the world? Is it generally no more than a few degrees, or potentially completely wildly out?

Following on from this, can I get a compass that does work pretty much worldwide to save the hassle of swapping back and forth between them, or is it just a case of always the right compass for the right place?


1 Answer 1


A compass is "accurate" in both hemispheres in that it should still point to magnetic north.

But the problem is that when you're in the southern hemisphere, the magnetic north pole is sort of 'under your feet' so the compass needs to be one that's specially 'balanced' for the Southern hemisphere to ensure the needle moves smoothly and responds fast.

You can get compasses that are 'globally balanced' to work everywhere - the Suunto M3 global is one.

The thing to remember in terms of 'outness' is magnetic declination. That varies hugely according to where you are in the world, and getting that wrong can send you way off course.

Similar question here, by the way.

  • 2
    This isn't, strictly speaking, accurate. It's convenient to think of a compass as pointing towards the magnetic north pole, but you could just as easily say it points towards magnetic south. The real issue here is that the needle will align itself along magnetic field lines, which run at an angle to the surface of the Earth which varies based on latitude. So a globally balanced compass can adjust for these different angles, while a standard compass will not work if you go too far north or south. Just a clarification.
    – Patrick N
    Aug 6, 2015 at 13:18
  • That Suunto link seems to be dead - do you have a replacement? I tried suunto.com/en-gb/Products/Compasses/Suunto-M-3-Global/… - but that just seems to be an empty placeholder with no information. Dec 5, 2018 at 16:35

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