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"
"
gm

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('^(?P<mounting_type>Z)(?P<number_of_function>1)(?P<unit_type>S)(?P<unit_size>6)(?P<function_in_port>AB-P|B-A|T-P|A|B|C|D|E|F|P|T)(?P<cracking_pressure>05|15|30|50)(?P<sep_1>-)(?P<unit_series>4X)(?P<sep_2>/|=)(?P<seal_material>V|N|MT)(?P<surface_coating>J3|)(?P<pipe_port>/60|/62|)(?P<special_version>SO68|SO90|SO104|)(?P<additional_details>(.|[0-9])*)$ ', 'gm') const str = `Z1S6E05-4X/V Z1S6E30-4X/V Z1S6E50-4X/V Z1S6F05-4X/V Z1S6F30-4X/V Z1S6F50-4X/V Z1S6P05-4X/V Z1S6P30-4X/V Z1S6P50-4X/V Z1S6T05-4X/V Z1S6T30-4X/V Z1S6T50-4X/V Z1S6A05-4X/V Z1S6A30-4X/V Z1S6A50-4X/V Z1S6B05-4X/V Z1S6B30-4X/V Z1S6B50-4X/V Z1S6C05-4X/V Z1S6C30-4X/V Z1S6C50-4X/V Z1S6D05-4X/V Z1S6D30-4X/V Z1S6D50-4X/V Z1S6C05-4X/VSO119 Z1S6P05-4X/VSO104 Z1S6P05-4X/VSO68 Z1S6P05-4X/VSO90 Z1S6P30-4X/VSO104 Z1S6P30-4X/VSO68 Z1S6P30-4X/VSO90 Z1S6T05-4X=V Z1S6P15-4X/V Z1S6P05-4X/V/62 Z1S6T15-4X/V Z1S6AB-P05-4X/V Z1S6T30-4X/N Z1S6P05-4X/N Z1S6E15-4X/V Z1S6F05-4X=V Z1S6C05-4X/N Z1S6C30-4X/VSO68 Z1S6C05-4X/VSO68 Z1S6A15-4X/V Z1S6C15-4X/V Z1S6D15-4X/V Z1S6D05-4X/N Z1S6D05-4X=V Z1S6B15-4X/V Z1S6F15-4X/V Z1S6T05-4X/N Z1S6T15-4X/VSO68 Z1S6A15-4X/V/62SO68 Z1S6E05-4X/N Z1S6T05-4X/VSO90 Z1S6T05-4X/VSO68 Z1S6P30-4X/N Z1S6F50-4X/VJ3 Z1S6B05-4X/N Z1S6F05-4X/N Z1S6T50-4X/N Z1S6C15-4X/N Z1S6D15-4X=V Z1S6D30-4X/N Z1S6C05-4X/NSO68 Z1S6P05-4X/MTSO68 Z1S6D05-4X/VJ3 Z1S6T50-4X=V Z1S6A05-4X=V Z1S6B15-4X/N Z1S6E15-4X/N Z1S6D30-4X=V Z1S6P15-4X/VSO104 Z1S6T15-4X/N Z1S6T30-4X/VSO90 Z1S6A15-4X/VJ3 `; // 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