Grid Point Code
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Putuo

ShanghaiChina

Grid Point Code for Putuo
With a code
#L9HL4-28PLT
Said aloud
Putuo 28PLT

Get the code for your door

What the code says

The Grid Point Code for Putuo is #L9HL4-28PLT. It names a cell 2.56 m north to south and 2.92 m east to west, centred on 31°15'03.63"N, 121°23'22.91"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 Putuo, near its centre.

Code
#L9HL4-28PLT
With a check character
#L9HL4-28PLT*T
Short form
28PLT
Cell centre
31.251007, 121.389696
Cell size
2.56 m by 2.92 m
Region
Shanghai
Country
China
Population
1,239,100

How to give this address

On a sign, a form or a delivery note

The whole code, #L9HL4-28PLT. It needs nothing else: no city, no street, no network to read it back.

Said aloud, in Shanghai

Putuo 28PLT: 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 4.6 km east or west of Putuo. 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

#L9HL4-28PLT*T. 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 45.7 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. L9HLMetropolitan area40 km by 45.7 km
  2. L9HL4District8 km by 9.14 km
  3. L9HL42Suburb1.6 km by 1.83 km
  4. L9HL428A few streets320 m by 365 m
  5. L9HL428PBuilding64 m by 73.1 m
  6. L9HL428PLEntrance12.8 m by 14.6 m
  7. L9HL428PLTDoorway2.56 m by 2.92 m

More in China

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