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

/
/
ig

Test String

Code Generator

Generated Code

const regex = /(?:^|\n)\s*Name\s*(?<name>[\w\W]+?)\s+Address\n(?<address>[\w\W]+?)\s+Date of Birth\s+(?<dob>[\w\W]+?)\s+Nationality\s*(?<nationality>[\w\W]+?)(?=\s)/ig; // Alternative syntax using RegExp constructor // const regex = new RegExp('(?:^|\\n)\\s*Name\\s*(?<name>[\\w\\W]+?)\\s+Address\\n(?<address>[\\w\\W]+?)\\s+Date of Birth\\s+(?<dob>[\\w\\W]+?)\\s+Nationality\\s*(?<nationality>[\\w\\W]+?)(?=\\s)', 'ig') const str = `Name Christopher Robert York Address Lyric House 6b St Andrew Street Hertford Hertfordshire SG14 1JA Date of Birth 24/12/1961 Nationality British Directorships for Mr Christopher Robert York Company Number Name Status Position Appointed Date Credit Limit Risk Score 12432488 �� CASTLE LEGAL SERVICES LTD Non trading Director 29/01/2020 £0 0 03075887 �� CREDITSERVE LTD. Company is dissolved Company Secretary 31/07/2006 £0 0 03075887 �� CREDITSERVE LTD. Company is dissolved Director 04/07/1995 £0 0 06534336 �� CREDITSERVE BUSINESS INFORMATION LIMITED Active - Accounts Filed Company Secretary 29/09/2008 £7,500 55 06534336 �� CREDITSERVE BUSINESS INFORMATION LIMITED Active - Accounts Filed Director 13/03/2008 £7,500 55 Ms Laura York Name Laura York Address Lyric House 6b St Andrew Street Hertford Hertfordshire SG14 1JA Date of Birth 01/06/1964 Nationality British Directorships for Ms Laura York Company Number Name Status Position Appointed Date Credit Limit Risk Score 06534336 �� CREDITSERVE BUSINESS INFORMATION LIMITED Active - Accounts Filed Director 01/04/2011 £7,500 55 Company Secretary`; // 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