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
Processing...

Test String

Code Generator

Language

Generated Code

$re = '/^((\.{2}\\\\)+|(\.?\\\\)?).+[^:\r\n]$/m'; $str = 'Directories: \\\\Reports\\Test\\\\Test ..\\meeting_minutes ..\\..\\profile Reports\\2023\\summary \\Reports\\2023\\summary .\\Reports\\2023\\summary ..\\Projects\\project_a ..\\Projects\\project a ..\\Projects\\..\\.\\project\\.\\..\\a .\\my_file ..\\Music#a\\file ..\\Music[Genre]\\file ..\\Music(Genre)\\file ..\\Music-Hardcore-Metal\\file ..\\Documents\\My+File ..\\Documents\\Some{Document} ..\\Files\\Afilewithweird;Characters\'` ..\\Music#^@!()-+{};\',.`~a\\file . ..\\ ..\\.. ..\\..\\ \\\\Reports\\Test\\\\Test ..\\..\\Final .\\..\\Test .\\..\\Test\\ ..\\..\\.\\Final\\..\\Shapefiles\\.\\Landuse ..\\..\\.\\Final\\..\\Shapefiles\\.\\Landuse\\ ..\\..\\data ./data-files/geological/EQs_last_week_of_2021.csv../data-files/geological/ EQs_last_week_of_2021.csv../../data-files/EQs_last_week_of_2021.csv../../../data-files/ media\\🎵 music\\lo-fi & chill\\set_03 (remastered) ..\\..\\data\\[raw]_input_🧪\\test-sample(01) src\\core.modules\\engine@v4 docs\\2025_06\\📝meeting_notes (draft)\\summary docs\\2025_06\\📝meeting_notes (draft)\\summary\\ Files\\ Files EQs_last_week_of_2021.csv../../../data-files/geological/EQs_last_week_of_2021 ../pictures/file .\\temp\\[backup]_2024\\final-version (2) assets\\images\\new.logo-2025_v2\\icon@2x#1 ..\\users\\username\\Documents (Archived)\\plan[final] projects\\#active-clients\\ACME_Corp\\Q2 Report\\summary v1.3\\ config\\env-settings\\!urgent media\\🎵 music\\lo-fi & chill\\set_03 (remastered) ..\\..\\data\\[raw]_input_🧪\\test-sample(01) src\\core.modules\\engine@v4 docs\\2025_06\\meeting_notes (draft)\\📝summary_notes themes\\🌑 darkmode (beta)\\style-final! ..\\..\\logs\\🪵 log-archive\\2023-12-25Christmas ..\\..\\logs\\🪵 log-archive\\2023-12-25[Christmas] ..\\..\\logs\\🪵 log-archive\\2023-12-25 [Christmas] downloads\\zips\\patch_update v34-final! build\\#output$\\v2.1.1\\installer(64bit) components\\UI-Toolkit_🔥\\modaldialog scripts\\batch jobs\\cleanup-temp_files! resources\\📁 static\\fonts\\Roboto_Bold-Italic tests\\[integration]_suite#2\\test-case(01) temp\\$$merge_conflict\\attempt_#3\\resolved✅ locales\\en-US\\messages(v1 backup\\[legacy]_configs\\1999 src\\modules\\@internal\\storage-handler ..\\releases\\build#2025.06.14\\installer-vFinal app\\#dev[tools]\\init Files: ..\\users\\username\\Documents (Archived)\\plan[final]\\theplan.txt projects\\#active-clients\\ACME_Corp\\Q2 Report\\summary v1.3\\summary.txt config\\env-settings\\!urgent\\OVERVIEW.XLSX media\\🎵 music\\lo-fi & chill\\set_03 (remastered)\\Cool Song.mp3 ..\\..\\data\\[raw]_input_🧪\\test-sample(01)\\Sample.db src\\core.modules\\engine@v4\\engine.exe docs\\2025_06\\meeting_notes (draft)\\📝summary_notes.txt themes\\🌑 darkmode (beta)\\style-final!.update build\\#output$\\v2.1.1\\installer(64bit)\\install_x64.msi resources\\📁 static\\fonts\\Roboto_Bold-Italic.ttf '; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php