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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /BN((6(0[0-9]|1[0134]|2[1-9]|3[0-1]))|7(0[68]|1(0|1[A-C])|2([1-4]|5|[7-9])|3[01]))/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('BN((6(0[0-9]|1[0134]|2[1-9]|3[0-1]))|7(0[68]|1(0|1[A-C])|2([1-4]|5|[7-9])|3[01]))', 'g') const str = `BN601 BN602 BN603 BN604 BN605 BN606 BN607 BN608 BN609 BN610 BN611 BN612 BN613 BN614 BN615 BN616 BN617 BN618 BN619 BN620 BN621 BN622 BN623 BN624 BN625 BN626 BN627 BN628 BN629 BN630 BN631 BN632 BN701 BN702 BN703 BN704 BN705 BN706 BN707 BN708 BN709 BN710 BN711 BN711A BN711B BN711C BN711a BN711b BN711c BN712 BN713 BN714 BN715 BN716 BN717 BN718 BN719 BN720 BN721 BN722 BN723 BN724 BN725 BN726 BN727 BN728 BN729 BN730 BN731 BN732 `; // 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