Grid Point Code
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Perth

Western AustraliaAustralia

Grid Point Code for Perth
With a code
#79GM6-52GJ4
Said aloud
Perth 52GJ4

Get the code for your door

What the code says

The Grid Point Code for Perth is #79GM6-52GJ4. It names a cell 2.56 m north to south and 2.90 m east to west, centred on 31°57'08.02"S, 115°51'40.99"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 Perth, near its centre.

Code
#79GM6-52GJ4
With a check character
#79GM6-52GJ4*K
Short form
52GJ4
Cell centre
-31.952229, 115.861386
Cell size
2.56 m by 2.90 m
Region
Western Australia
Country
Australia
Population
2,384,371

How to give this address

On a sign, a form or a delivery note

The whole code, #79GM6-52GJ4. It needs nothing else: no city, no street, no network to read it back.

Said aloud, in Western Australia

Perth 52GJ4: 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 4.5 km east or west of Perth. 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

#79GM6-52GJ4*K. 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 45.3 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. 79GMMetropolitan area40 km by 45.3 km
  2. 79GM6District8 km by 9.07 km
  3. 79GM65Suburb1.6 km by 1.81 km
  4. 79GM652A few streets320 m by 363 m
  5. 79GM652GBuilding64 m by 72.5 m
  6. 79GM652GJEntrance12.8 m by 14.5 m
  7. 79GM652GJ4Doorway2.56 m by 2.9 m

More in Australia

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