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"
"
gmi

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('(?<!\\bsub )\\btotal\\b\\D*(\\d+(?:\\.\\d+))', 'gmi') const str = `Friscos #8603 8100 E. Orchard Road Greenwood Village, Colorado 80111 2013-11-02 Table 00 Guest 1 Oysters 1/2 Shell #1 1 Crab Cake 1 Filet 1602 Bone In 1 Ribeye 22oz Bone In 1 Asparagus 1 Potato Au Gratin \$17.00 \$19.00 \$66.00 \$53.00 \$12.00 \$11.50 Sub Total Tax \$178.50 \$12.94 Total \$191.44 Berghotel Grosse Scheidegg 3818 Grindelwald Familie R. Müller Rech. Nr. 4572 Bar 30.07.2007/13:29:17 Tisch 7/01 NM #ರ 2xLatte Macchiato à 4.50 CHF 1xGloki à 5.00 CHF 1xSchweinschnitzel à 22.00 CHF 1xChässpätzli à 18.50 CHF #ರ #ರ #1ರ 5.00 22.00 18.50 Total: CHF 54.50 Incl. 7.6% MwSt 54.50 CHF: 3.85 Entspricht in Euro 36.33 EUR Es bediente Sie: Ursula MwSt Nr. : 430 234 Tel.: 033 853 67 16 Fax.: 033 853 67 19 E-mail: grossescheidegg@bluewin.ch ' `; // 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