Random Indian Pincode Generator

How this random Indian PIN code generator works

Press Generate and you get a full record: the post office, its six-digit PIN code, the city, the district and the state. Turn up the Number box for several at once, no repeats.

Rudra Prayag, 246171. Chinchpokli in Mumbai, 400011. Poyilisseri. Gharghoda. Jaswantgarh Nagaur.

There is no starts-with or contains box here, because every result is a five-field record rather than a single string. And the reason to care about those five fields is that four of them can change while the fifth cannot.

The number outlived the map

India has spent the last quarter of a century renaming itself, one state at a time.

Uttaranchal became Uttarakhand with effect from 1 January 2007. Orissa became Odisha in 2011. Pondicherry became Puducherry on 1 October 2006. Calcutta became Kolkata in 2001. Chhattisgarh was created out of Madhya Pradesh in November 2000. And on 2 June 2014, ten districts of Andhra Pradesh, Hyderabad and Karimnagar among them, became the state of Telangana.

Every one of those events invalidated a column in every address database in the country.

Not one of them changed a single PIN code.

Rudra Prayag is 246171 whether the state above it says Uttaranchal or Uttarakhand. Hyderabad's numbers did not move when Telangana was carved out around them. Calcutta becoming Kolkata did not disturb 700048.

The words moved. The digits did not. A postal code turns out to be a more durable description of where you live than the name of your state, and the reason is that the number was never describing the state. It was describing the route a letter takes to reach a counter, and the counter did not go anywhere.

This is the difference between an identifier and a label. Identifiers persist. Labels are politics.

What the six digits mean

Every PIN code is exactly six digits, and every digit is doing a job.

• The first digit is the postal zone. There are nine.
• The second digit, with the first, gives the sub-zone or postal circle, which usually corresponds to a state.
• The third digit, with the first two, gives the sorting district.
• The last three digits identify the individual post office inside that district.

So the code narrows as you read it, left to right, from a slab of the subcontinent down to a single counter. No digit is decoration. Nothing starts with zero.

Take 400011. The 4 is the zone covering Maharashtra, Goa, Madhya Pradesh and Chhattisgarh. The next digits narrow that to a circle, then to a sorting district, and the final three land on Chinchpokli.

Zone 9 is not a place

Eight of the nine zones are geography. The ninth is not.

A PIN code beginning with 9 belongs to the Army Postal Service. It routes mail to Army Post Offices and Field Post Offices, and a field post office is a mobile thing that travels with the unit it serves.

Which means a 9-series PIN code does not correspond to any fixed point on Earth. It corresponds to a formation. The soldiers move, the number stays with them, and the letter finds them anyway.

A ninth of India's postal numbering describes an institution rather than a territory. It is the one part of the system where the address is a who rather than a where.

Why India needed a number at all

Consider the problem that faced the Department of Posts.

India is enormous and its place names repeat relentlessly. A letter addressed to Rampur could be intended for any of dozens of Rampurs. And the address itself might arrive written in Devanagari, or Tamil, or Bengali, or Gurmukhi, or the Roman alphabet.

A sorter had to read the handwriting, guess the script, recognise the place name, and then work out which of the identically named places was meant.

A number solves all of it at once. Digits are the same in every script. They cannot be confused with a different town of the same name. They can be read by somebody who does not speak the language of the address.

The Postal Index Number was introduced on 15 August 1972, the twenty-fifth anniversary of independence.

The man who wrote the code wrote poems that ran backwards

The PIN system was the work of Shriram Bhikaji Velankar, an additional secretary in the Union Ministry of Communications and a senior member of the Posts and Telegraphs Board.

He was also a Sanskrit poet, and a serious one. He received the President's Award for Sanskrit in 1996 and wrote, by the accounts published when the PIN code turned fifty, more than a hundred books and plays.

Among his works was a viloma kavya: verse constructed so that, read forwards, it praises Rama, and read backwards, the same syllables become praise of Krishna.

There is something worth sitting with in a man who spent his working life designing a code in which every digit narrows the meaning of the digit before it, and spent his evenings writing lines that mean two different things depending on which end you start from.

He gave India a number for every post office. It has outlasted several of the states.

Ways people actually use this

• Test data. Real post offices, real codes, real districts, including Telangana.
• Quizzes. Show the PIN, ask for the zone. The first digit gives it away once you know the trick.
• Teaching data design. The neatest demonstration anywhere of the difference between an identifier and a label. Identifiers persist. Labels are politics.
• Writing. Every record is a real place with a real post office, and most of them have never appeared in a novel.
• Address forms. If you validate an Indian PIN, the rules are simple: six digits, first digit 1 to 9, no leading zero.

Questions people ask

What does PIN stand for?

Postal Index Number. Saying "PIN code" repeats the word code, which almost everybody does anyway.

What do the six digits of a PIN code mean?

The first is the postal zone, the second gives the sub-zone or circle, the third completes the sorting district, and the last three identify the specific post office.

What does a PIN code starting with 9 mean?

It belongs to the Army Postal Service, covering Army Post Offices and Field Post Offices. Eight zones are geographic. The ninth is functional, and it moves.

When was the PIN code introduced?

On 15 August 1972, by Shriram Bhikaji Velankar of the Ministry of Communications, to solve the problem of duplicate place names and addresses written in many different scripts.

Do PIN codes change when a state is renamed?

No. The code describes the route to a post office, not the political geography around it. Hyderabad's PIN codes were unaffected when Telangana was created in 2014, and Kolkata's were unaffected when Calcutta was renamed in 2001.

References

1. Postal Index Number
2. What is a PIN code, Manorama Yearbook
3. PIN code in India explained
4. List of renamed places in India