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This question is not as simple as it seems, and a few minutes of googling did not drop the answer in my lap.

A comment at I never adjust for true north. Is this bad practice? suggesting that:

True north and magnetic north are basically the same thing

started me on a search for a quality answer I could use in a response. I believe the distance between them is larger than size of many small countries, so not sure I would call them basically the same thing.

How much distance (miles/kilometers) is there between True North(Geographic) and Magnetic North Poles?

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    The distance in kilometers is not what's really relevant for navigation. For navigation, we normally care about the angular difference. That can be as much as 180 degrees in northern Canada. – Ben Crowell Dec 17 '15 at 17:16
  • Distance gives perspective. See my comment here you are correct that angular difference is the most significant, and it does not get any worse than 180 degrees of out of 360. – James Jenkins Dec 17 '15 at 18:16
  • wouldn't the angular difference have a direct relationship with the distance? Would it be possible to have same distance for various angular differences or vice versa? – user17915 Dec 18 '15 at 11:03
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Magnetic pole

The distance from the rotational north pole varies over time

enter image description here

-source

By the time you read this, the north magnetic pole could be half the circumference of the planet away from the true (i.e. rotational) north pole. Thats over 20,000 km apart. It has been in the past. See magnetic pole reversal and rate of transition.

Declination

More important than the actual position of the magnetic north pole is the direction your magnetic compass points at various places on Earth - they don't all point towards the magnetic north pole - magnetic north is a local attribute which varies from place to place (and from year to year)

Declination map

In many parts of the world, magnetic declination is more than 10 degrees, in some places much more - this is sufficient to cause hikers difficulties.

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    South Africa, most of Brazil, North America from the Rockies on west, the west coast of Australia, and New Zealand all have magnetic declinations in excess of 10 degrees. Sure, you're not going to go east when your compass says north, but ten degrees is the difference between going down the right valley, and going down the wrong one. – Mark Dec 18 '15 at 4:24
  • @Mark absolutely - in Fiordland (NZ; popular outdoors area) it's currently 25 degrees. That's big enough that if sighting along a compass needle the true north is way off in peripheral vision – Tom Goodfellow Dec 18 '15 at 11:09
  • The kilometer was defined such that the distance between the North Pole and the Equator via Paris is 10,000 kilometers. Thus, no place on Earth is "over 20,000 km" from the North Pole. – Jasper Jan 14 at 23:46
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The distance between the magnetic north and geographic north poles is not important for navigation purposes. What matters is the angle between them, which is called the magnetic variation or magnetic declination.

The magnetic variation varies depending on where you are on earth, and also changes slightly from year to year. In Pittsburgh, Pennsylvania, it's approximately 9° west.

In some places, if you are standing at a point that is collinear with the two poles, the magnetic variation is 0°. On the other hand, very close to the magnetic pole, it could be anything: compasses are nearly useless there.

For aviation and navigation, correcting for the magnetic variation is crucial. For hiking, probably not so much (in most places on earth), since you're not going to be following a constant bearing for miles and miles.

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    For the artillery it is very important too... nuff said – RedSonja Dec 18 '15 at 7:13
  • Mag to Grid (Get Rid), Grid to Mag (Add) as the old saying goes. – Venture2099 Jan 25 '17 at 15:40
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They're absolutely NOT the same thing.

The distance varies. But it's about 500 miles. (The North Pole: Location, Weather, Exploration … and Santa).

Since its discovery in 1831, the magnetic North Pole has been around Canada’s Ellesmere Island, about 500 miles (800 kilometers) from the geographic North Pole.

True north (Wikipedia)

  • On VFR charts (flight maps) the magnetic variance is marked on the map. – tallen Dec 17 '15 at 17:14

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