Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
mg

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(PostgreSQL (?P<psql_major>\\d{1,2})\\.(?P<psql_minor>\\d{1,2})(?P<psql_opt_patch>\\.\\d{1,2})?, )?Aurora PostgreSQL release (?P<aurora_psql_major>\\d{1,2})\\.(?P<aurora_psql_minor>\\d{1,2})(?P<aurora_psql_opt_patch>\\.\\d{1,2})?(?P<release_or_deprecation>\\,\\s(?P<release_data>.*)|\\s\\(Deprecated on (?P<deprecation_date>.*)\\))?', 'mg') const str = `PostgreSQL 12.6, Aurora PostgreSQL release 4.1 (Deprecated on July 15, 2022) PostgreSQL 12.4, Aurora PostgreSQL release 4.0 (Deprecated on July 15, 2022) Aurora PostgreSQL release 14.3.1, July 6, 2022 PostgreSQL 9.6.8, Aurora PostgreSQL release 1.2 (Deprecated on October 28, 2021) PostgreSQL 9.6.8, Aurora PostgreSQL release 1.2.4 PostgreSQL 14.5, Aurora PostgreSQL release 1.2 Aurora PostgreSQL release 14.3.1, Deprecated on October 28, 2021)`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions