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Pattern

Regex for DIN (Director Identification Number)

8-digit ID for company directors.

The pattern

^\d{8}$
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What it matches

  • 12345678
  • 00000001
  • 98765432

What it doesn't match

  • 1234567
  • 123456789
  • ABC12345

Notes & gotchas

Issued by the Ministry of Corporate Affairs to every individual appointed as a director of an Indian company. Permanent unless cancelled. Format is exactly 8 digits.

Code in your language

Use the explainer's Code tab to generate ready-to-paste snippets in JavaScript, Python, Java, .NET, Go, Ruby, and PHP for this pattern.

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About this pattern

India-specific identifiers are governed by various authorities (UIDAI for Aadhaar, Income Tax Dept for PAN, RBI for IFSC, GSTN for GSTIN, etc.). Regex confirms format; for definitive validation, integrate with the issuing authority's verification API.

Quick usage in different languages

Once you've validated a candidate value matches this pattern, you'll typically use it inside your application code. Each language has its own regex syntax:

  • JavaScript: new RegExp(pattern).test(value)
  • Python: re.match(pattern, value) with raw strings: r"pattern"
  • Java: Pattern.compile(pattern).matcher(value).matches()
  • C# / .NET: Regex.IsMatch(value, pattern)
  • Go: regexp.MustCompile(pattern).MatchString(value) — Go uses RE2 so some advanced features aren't available
  • Ruby: value =~ /pattern/ or pattern.match?(value)
  • PHP: preg_match('/pattern/', $value)

The explainer's Code tab generates these for any pattern you paste — including the right escaping and idioms for each language.

Common pitfalls

  • Anchors matter. If the pattern uses ^ and $ it expects the entire input to match. To find this pattern inside a longer text, remove the anchors and use the /g flag.
  • Case sensitivity. Letter ranges like [A-Z] only match uppercase. Use the i flag or [A-Za-z] for case-insensitive matching.
  • Escape user input. If you're building a regex from a string variable, escape regex metacharacters first to avoid bugs or injection.
  • Performance. For this specific pattern the risk is low, but be cautious of nested quantifiers when adapting it — they can cause exponential backtracking on adversarial input.

See also

Browse all 300 patterns in the library, or open this regex in the interactive explainer for a token-by-token breakdown, live testing, and code in seven languages.


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