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

/
/
gmi

Test String

Code Generator

Language

Generated Code

const regex = /^(?:ach\sdebit\s|point\sof\ssale\sdebit\s)?(?:l\d{3}\s)?(?:TIME\s\d\d:\d\d\s[A|P]M\s*)?(?:DATE\s\d\d-\d\d\s)?([a-z-*'\s]+)(?:[\d\s]{15,}|\d{3}-?\d{3}-?\d{4}|#\w+)?/gmi; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?:ach\\sdebit\\s|point\\sof\\ssale\\sdebit\\s)?(?:l\\d{3}\\s)?(?:TIME\\s\\d\\d:\\d\\d\\s[A|P]M\\s*)?(?:DATE\\s\\d\\d-\\d\\d\\s)?([a-z-*\'\\s]+)(?:[\\d\\s]{15,}|\\d{3}-?\\d{3}-?\\d{4}|#\\w+)?', 'gmi') const str = `ACH Debit 5/3 MORTGAGE LN PAYMENT 017136000924355 Point of Sale Debit L340 TIME 08:37 AM DATE 04-26 JR GENERAL STORE CHARLOTTE NC Point of Sale Debit L343 TIME 07:02 PM DATE 04-25 AUTOZONE 4982 35CONCORD NC Point of Sale Debit L343 TIME 07:00 PM DATE 04-25 AUTOZONE 4982 35CONCORD NC Point of Sale Debit L340 DATE 04-25 ASF*ATA KARATE OF 800-5258967 ACH Debit GS Home Imp Fin 8669360602 017116001434401 Point of Sale Debit L343 TIME 07:56 AM DATE 04-27 AUTOZONE 4982 35CONCORD NC Point of Sale Debit L340 DATE 04-25 CHICK-FIL-A #01118CONCORD Point of Sale Debit L340 DATE 04-26 ANGELAS CONCORD Point of Sale Debit L340 DATE 04-25 ATA KARATE CONCORDCONCORD Check INCLEARING CHECK Point of Sale Debit L341 TIME 03:52 PM DATE 04-27 HARRIS TE 358 GEOCONCORD NC Point of Sale Debit L341 TIME 08:57 AM DATE 04-28 WALGREENS STORE 1CHARLOTTE NC Point of Sale Debit L340 DATE 04-26 CHICK-FIL-A #01118CONCORD Point of Sale Debit L340 DATE 04-27 HT EXPRESS LANE #6CONCORD `; // 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