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Pattern

Regex for FSSAI license

14-digit Food Safety license number.

The pattern

^[1-2]\d{13}$
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What it matches

  • 12345678901234
  • 21234567890123
  • 11122233344455

What it doesn't match

  • 0123456789012
  • 123456789012
  • 1234567890ABCD

Notes & gotchas

14-digit FSSAI license/registration number. Starts with 1 (state license) or 2 (central license). Must be displayed on food product packaging in India. Issued by the Food Safety and Standards Authority of India.

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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