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

/
/
gm

Test String

Code Generator

Language

Generated Code

const regex = /RJ.currentMP3Url = \'([\w\\\/-]+)'/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('RJ.currentMP3Url = \\\'([\\w\\\\\\\/-]+)\'', 'gm') const str = ` </div> </div> </div> </div> </section> <script> RJ.currentMP3Url = 'mp3/Arian-Band-To-Ke-Ba-Man-Baashi'; RJ.currentMP3 = '40008'; RJ.currentMP3Type = 'mp3'; RJ.playingIndex = '0'; RJ.currentMP3Perm = 'Arian-Band-To-Ke-Ba-Man-Baashi'; RJ.currentAlbum = null; RJ.currentPlaylist = null; RJ.relatedMP3 = [{"next":"Arian-Band-To-Ke-Ba-Man-Baashi","index":0},{"next":"Arian-Band-Bargard","index":1},{"next":"Arian-Band-Bishtar","index":2},{"next":"Arian-Band-Deltangiha","index":3},{"next":"Arian-Band-Faseleh","index":4},{"next":"Arian-Band-Delam-Barat-Tang-Shodeh","index":5},{"next":"Arian-Band-To-Moondi-o-Man","index":6},{"next":"Arian-Band-Nemidoonam","index":7},{"next":"Arian-Band-Baade-To","index":8},{"next":"Arian-Band-Too-Cheshaye-Man-Negah-Kon","index":9},{"next":"Arian-Band-Ta-Abaad","index":10},{"next":"Arian-Band-Gole-Man","index":11},{"next":"Arian-Band-Parvaz","index":12},{"next":"Arian-Band-Gole-Aftab-Gardoon","index":13},{"next":"Arian-Band-Parvaz-(Club-Mix)","index":14},{"next":"Arian-Band-Ghasedak","index":15},{"next":"Arian-Band-Baroon","index":16},{"next":"Arian-Band-Panjereh","index":17},{"next":"Arian-Band-Setareh","index":18},{"next":"Arian-Band-Ey-Javidan-Iran","index":19},{"next":"Arian-Band-Tab","index":20},{"next":"Arian-Band-Gole-Hamishe-Bahar","index":21},{"next":"Arian-Band-Afsoongar","index":22},{"next":"Arian-Band-Iran","index":23},{"next":"Arian-Band-The-Words-I-Love-You-(Feat-Chris-de-Burgh)","index":24},{"next":"Arian-Band-Bi-To-Ba-To","index":25},{"next":"Arian-Band-Aroom-Aroom","index":26},{"next":"Arian-Band-Lahzeh-ha","index":27},{"next":"Arian-Band-Bahooneh","index":28},{"next":"Arian-Band-Na-Mehraboon","index":29},{"next":"Arian-Band-Farda-Male-Mast","index":30}]; RJ.nextMp3Base = '/mp3s/mp3/'; RJ.nextMp3AlbumBase = '/mp3s/album/'; RJ.playerVolume = 75; setupMP3Ping(); </script> `; // 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