Grid Point Code
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Tokyo

Japan

Grid Point Code for Tokyo
With a code
#L8R34-NDX3K
Said aloud
Tokyo NDX3K

Get the code for your door

What the code says

The Grid Point Code for Tokyo is #L8R34-NDX3K. It names a cell 2.56 m north to south and 2.78 m east to west, centred on 35°41'22.20"N, 139°41'30.19"E, and it turns back into that cell on any phone or computer by arithmetic alone: no network, no account, no lookup table.

The point used is the one GeoNames records for Tokyo, near its centre, and Tokyo is the capital of Japan.

Code
#L8R34-NDX3K
With a check character
#L8R34-NDX3K*X
Short form
NDX3K
Cell centre
35.689501, 139.691720
Cell size
2.56 m by 2.78 m
Country
Japan
Population
9,733,276

How to give this address

On a sign, a form or a delivery note

The whole code, #L8R34-NDX3K. It needs nothing else: no city, no street, no network to read it back.

Said aloud, in Japan

Tokyo NDX3K: a name both people know, then the last five characters. They give back the exact code for anywhere within 4.0 km north or south and 4.3 km east or west of Tokyo. Further away the same five name somewhere else, which is why the whole code is what goes on a sign.

Copied by hand, or read over a phone

#L8R34-NDX3K*X. The character on the end catches any single mistyped symbol and any two neighbours swapped.

As a link or a square code

Open it on the map, move to the exact door, and add directions if the code needs help: "blue gate, second floor". The link and the square code carry them. Nothing is kept on this site.

From the city to the door

The first four characters name a cell about 40 km by 43.4 km here. Each one after that picks one of 25 inside the last, so the whole ten name a spot about the size of a doorway.

  1. L8R3Metropolitan area40 km by 43.4 km
  2. L8R34District8 km by 8.68 km
  3. L8R34NSuburb1.6 km by 1.74 km
  4. L8R34NDA few streets320 m by 347 m
  5. L8R34NDXBuilding64 m by 69.4 m
  6. L8R34NDX3Entrance12.8 m by 13.9 m
  7. L8R34NDX3KDoorway2.56 m by 2.78 m

More in Japan

City, region and population from GeoNames, under CC BY 4.0.