Regex for Indian PIN Codes

Read it left to right. Each piece below matches one part of the input:

• ^[1-9] The first digit, the postal region, from 1 to 9. No PIN code starts with 0.
• \d{2} The next two digits: the sub-region and the sorting district.
• \s? An optional space, as in 560 001.
• \d{3} The last three digits identify the delivery post office.
• $ End of the string.

The whole input must match, from the first character to the last. Every row below is checked against the pattern by our automated test suite before each release.

India Post introduced the Postal Index Number in 1972. Reading left to right:

That structure is why [1-9] is the only constraint the regex puts on individual digits: everything else depends on which offices exist, which changes over time.

The format check cannot tell you whether a post office uses that number. India Post publishes the full PIN code directory through the Open Government Data platform, and several free APIs return the post office, district and state for a code, which also lets you auto-fill the city and state fields in a checkout form.

On mobile, use inputmode="numeric" and autocomplete="postal-code", keep the field as text, and strip the optional space with pin.replace(/\s/g, "") before saving.

The pattern is translated for each engine rather than pasted as is: named groups, anchors, escapes, shorthand classes and flags are adjusted so each snippet behaves as closely to the JavaScript version as its engine allows. Differences that remain (Go's RE2 has no lookarounds or backreferences, for example) are called out under each one. The Code tab in the tester above also exports Dart, and updates as you edit the pattern.

JavaScript and TypeScript

const regex = /^[1-9]\d{2}\s?\d{3}$/;

function isValid(value) {
  return regex.test(value);
}

console.log(isValid("110001"));

Python

import re

pattern = re.compile(r"^[1-9][0-9]{2}\s?[0-9]{3}\Z")

def is_valid(value: str) -> bool:
    return pattern.search(value) is not None

print(is_valid("110001"))

• \d and \w are written as [0-9] and [A-Za-z0-9_] because in Python they also match digits and letters from other scripts.
• JavaScript's $ only matches at the very end of the string. Python's $ also matches before a trailing newline, so the pattern uses \Z instead.

Go

package main

import (
	"fmt"
	"regexp"
)

func main() {
	re := regexp.MustCompile(`^[1-9]\d{2}\s?\d{3}$`)
	fmt.Println(re.MatchString("110001"))
}

• Go's \s only matches space, \t, \n, \f and \r; JavaScript's also matches the non-breaking space and other Unicode spaces.

C#

using System;
using System.Text.RegularExpressions;

// The timeout stops a pathological input from hanging the thread (ReDoS).
var regex = new Regex(@"^[1-9][0-9]{2}\s?[0-9]{3}\z", RegexOptions.None, TimeSpan.FromSeconds(1));
Console.WriteLine(regex.IsMatch("110001"));

• \d and \w are written as [0-9] and [A-Za-z0-9_] because in .NET they also match digits and letters from other scripts.
• JavaScript's $ only matches at the very end of the string. .NET's $ also matches before a trailing newline, so the pattern uses \z instead.

PHP

<?php

$pattern = '/^[1-9]\d{2}\s?\d{3}$/D';

function isValid(string $value, string $pattern): bool
{
    return preg_match($pattern, $value) === 1;
}

var_dump(isValid('110001', $pattern));

• PCRE's \s matches ASCII whitespace unless Unicode properties (UCP) are on; JavaScript's also matches the non-breaking space and other Unicode spaces.
• The D modifier makes $ match only at the very end, like JavaScript (PCRE's $ also matches before a trailing newline).

• Regex for US ZIP Codes: Five-digit ZIP codes with an optional ZIP+4 extension, like 90210-1234.
• Regex for UK Postcodes: All six UK postcode formats, with or without the space, including SW1A 1AA.
• Regex for Phone Numbers (E.164 Format): International numbers in E.164: a plus, a country code and up to 15 digits in total.
• Regex for Numbers Only: Digits only, plus variants for signs, decimals and thousands separators.

Browse all 25 patterns in the regex pattern library, or build your own in the regex tester.