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
Processing...

Test String

Code Generator

Language

Generated Code

const regex = /(?:(AT)\s*(U[0-9]{8}))|(?:(BE)\s*(0?[0-9]{*}))|(?:(CZ)\s*([0-9]{8,10}))|(?:(DE)\s*([0-9]{9}))|(?:(CY)\s*([0-9]{8}[A-Z]))|(?:(DK)\s*([0-9]{8}))|(?:(EE)\s*([0-9]{9}))|(?:(GR)\s*([0-9]{9}))|(?:(ES)\s*([0-9A-Z][0-9]{7}[0-9A-Z]))|(?:(FI)\s*([0-9]{8}))|(?:(FR)\s*([0-9A-Z]{2}[0-9]{9}))|(?:(GB)\s*(([0-9]{9}|[0-9]{12})~(GD|HA)[0-9]{3}))|(?:(HU)\s*([0-9]{8}))|(?:(IE)\s*([0-9][A-Z0-9\\+\\*][0-9]{5}[A-Z]))|(?:(IT)\s*([0-9]{11}))|(?:(LT)\s*(([0-9]{9}|[0-9]{12})))|(?:(LU)\s*([0-9]{8}))|(?:(LV)\s*([0-9]{11}))|(?:(MT)\s*([0-9]{8}))|(?:(NL)\s*([0-9]{9}B[0-9]{2}))|(?:(PL)\s*([0-9]{10}))|(?:(PT)\s*([0-9]{9}))|(?:(SE)\s*([0-9]{12}))|(?:(SI)\s*([0-9]{8}))|(?:(SK)\s*([0-9]{10}))|(?:\D|^)([0-9]{11})(?:\D|$)|(?:(CHE)(-|\s*)([0-9]{3}\.[0-9]{3}\.[0-9]{3}))/gi; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?:(AT)\\s*(U[0-9]{8}))|(?:(BE)\\s*(0?[0-9]{*}))|(?:(CZ)\\s*([0-9]{8,10}))|(?:(DE)\\s*([0-9]{9}))|(?:(CY)\\s*([0-9]{8}[A-Z]))|(?:(DK)\\s*([0-9]{8}))|(?:(EE)\\s*([0-9]{9}))|(?:(GR)\\s*([0-9]{9}))|(?:(ES)\\s*([0-9A-Z][0-9]{7}[0-9A-Z]))|(?:(FI)\\s*([0-9]{8}))|(?:(FR)\\s*([0-9A-Z]{2}[0-9]{9}))|(?:(GB)\\s*(([0-9]{9}|[0-9]{12})~(GD|HA)[0-9]{3}))|(?:(HU)\\s*([0-9]{8}))|(?:(IE)\\s*([0-9][A-Z0-9\\\\+\\\\*][0-9]{5}[A-Z]))|(?:(IT)\\s*([0-9]{11}))|(?:(LT)\\s*(([0-9]{9}|[0-9]{12})))|(?:(LU)\\s*([0-9]{8}))|(?:(LV)\\s*([0-9]{11}))|(?:(MT)\\s*([0-9]{8}))|(?:(NL)\\s*([0-9]{9}B[0-9]{2}))|(?:(PL)\\s*([0-9]{10}))|(?:(PT)\\s*([0-9]{9}))|(?:(SE)\\s*([0-9]{12}))|(?:(SI)\\s*([0-9]{8}))|(?:(SK)\\s*([0-9]{10}))|(?:\\D|^)([0-9]{11})(?:\\D|$)|(?:(CHE)(-|\\s*)([0-9]{3}\\.[0-9]{3}\\.[0-9]{3}))', 'gi') const str = `CHE-459.288.946 IDI n. CHE-459.288.946 CHE 459.288.946 PI:01924110289 CF BGGLNI40S20I008I LV12345678901 12345678901`; // 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