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 = /^(?:.*[\/\\])?(?<FileNameWithoutExtension>.*)\.(.*)$/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?:.*[\\\/\\\\])?(?<FileNameWithoutExtension>.*)\\.(.*)$', 'gm') const str = `Taylor Swift - New Romantics.m4a YT/Subto2mp3/Taylor Swift - New Terribly Romantics.m4a Grow - Conan Blue (Official Video) has already been recorded in archive.m4a PowerOptim Iol/Techno/(Official Video) Blue Burrow was already been recorded in archive - Bak.wm4 /Great Bun/Output Files/çè/Grow - Conan DARK (Official AUDIO) has already been recorded in archive.m4b Matter Oil_9999.zip Qpl\$-pol.hrlp/perm.ui.pol/i op/doesn't matter.mp4 Small Laser4.m4a manicur pliu/love is in the a°°_II+?§@R.txt ^Level09\\\\Power Pol\\energy.m4a lollller_blllade 1987 (c)/super €/music_piece_.mp3 \\.\\.\$./../../loli( u1990) _98.lop.pl/fil l/fill2asm.aile.asm.gz.zip /Taylor Swift - New Romantics._m4a \\\$/Subto2/mp3/Taylor Swift -&- New Romantics.m4a /Grow - Conan Gray (Official Video) has already been recorded in archive.m4a C:\\PowerOptim Iol/Grow - The New Gray (Official Video) has been recorded [<1999>.wm4 /Great Bun/Output Files/çè/Grow - WiLlL(O)W Gray "unofficial" video has not been recorded in archive.m4b /Matter Oil_9999.zip file:///Qpl\$-pol.hrlp/perm.ui.pol/i op/matter.mp4 /£¥«^6<4>à_»Laser4 \`\`[12{2%}32]deg\`‘.webm manicur pliu/great.power.great.responsibility?.gz.tar.zip ./poi kiol/greater.power.greater.responsibility!.gz.tar.zip ^Level09\\Power Pol\\energy.m4a lollller_blllade 1987 (c)/super €/music_piece_.mp3 /The 'great' solitude of zorro #12/the 退ellent urge_for.mo.tar.gz `; // 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