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Pattern

Regex for HTTP 2xx (success)

200-series HTTP success status codes.

The HTTP 2xx (success) regex is ^2\d{2}$ — copy it below, or open it in the explainer for a token-by-token breakdown.

The pattern

^2\d{2}$
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What it matches

  • 200
  • 201
  • 204
  • 299

What it doesn't match

  • 100
  • 301
  • 404
  • 500

Notes & gotchas

200-299 represent successful responses. 200 OK, 201 Created, 204 No Content, 206 Partial Content are most common.

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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Token-by-token breakdown

Every part of the pattern, left to right:

TokenMeaning
^start of string (or line in multiline mode)
2literal text “2”
\d{2}exactly 2 times: digit (0–9)
$end of string (or line in multiline mode)

About this pattern

Developer-oriented patterns help with code analysis, log parsing, and data transformation. Use these in build scripts, CI tools, IDE search-and-replace, and code review utilities.

Quick usage in different languages

This exact pattern — with the correct escaping and idioms for each language:

  • JavaScript: /^2\d{2}$/.test(value)
  • Python: re.match(r"^2\d{2}$", value)
  • Java: Pattern.compile("^2\\d{2}$").matcher(value).matches()
  • C# / .NET: Regex.IsMatch(value, @"^2\d{2}$")
  • Go: regexp.MustCompile(`^2\d{2}$`).MatchString(value)
  • Ruby: /^2\d{2}$/.match?(value)
  • PHP: preg_match('~^2\d{2}$~', $value)

The explainer’s Code tab regenerates these for any pattern you paste, and the downloadable cheat sheet bundles the breakdown, all seven snippets, and the pitfalls below onto one printable page.

Common pitfalls

  • Anchored to the whole string. This pattern uses ^ and $, so it requires the entire input to match. To find it inside a longer text, drop the anchors and use the global (g) flag.
  • Escape it correctly per language. In Java and JavaScript strings each backslash must be doubled (\\d); in Python, Go, and C# use raw/verbatim strings so the backslashes survive.
  • Validate beyond format. Matching the format doesn't guarantee the value is real. Confirm the http 2xx (success) against a source of truth (database, API, or checksum) where it matters.

Standards & sources

This pattern is based on the following authoritative specification(s) and issuing authorities. Formats can change — always confirm against the primary source.

Related patterns

More patterns in the Developer category:

See also

Browse all 300 patterns in the library, or open this regex in the interactive explainer to see a token-by-token breakdown, test against custom input, and generate code in seven languages.


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