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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

import re regex = re.compile(r"\[([A-G][#b]?(maj|m)?[27]?(add|aug|dim|sus)?[2-9]?)\]") test_str = ("[Am7], [C6]\n" "[C7]\n" "[Cmaj7]\n" "[C]\n" "[Fadd9]\n" "[C7sus4]\n" "[Csus4], [Fsus2]\n" "[A7]\n" "[Edim]\n" "[A9], [Em6]\n" "[Dbdim]\n" "[Eb9]\n" "[Gdim]\n" "[A7sus4]\n" "[C9], [Gm6]\n" "[Em7], [G6]\n" "[Bb6], [Gm7]\n" "[G7]\n" "[G7sus4]\n" "[Gmaj7]\n" "[Dsus4], [Gsus2]\n" "[Gm]\n" "[G]\n" "[Csus2], [Gsus4]\n" "[Ebadd9]\n" "[Eb]\n" "[Ebaug], [Gaug]\n" "[Cm]\n" "[Em9]\n" "[Cadd9]\n" "[Abaug], [Caug], [Eaug]\n" "[Fm]\n" "[Amaj7]\n" "[Dbm6], [Gb9]\n" "[Dbm7]\n" "[Bbm7], [Db6]\n" "[Db7]\n" "[Db]\n" "[Gbadd9]\n" "[Gbsus2]\n" "[E7]\n" "[Bb7]\n" "[Abdim], [Fdim]\n" "[Fm6]\n" "[Gbm9]\n" "[Bm6], [E9]\n" "[Emaj7]\n" "[Dbm9]\n" "[Bb7sus4]\n" "[Db9]\n" "[Ab6], [Fm7]\n" "[Dbadd9]\n" "[Abm7], [B6]\n" "[Ab7]\n" "[Ab7sus4]\n" "[Abmaj7]\n" "[Absus2]\n" "[Absus4]\n" "[E]\n" "[Eadd9]\n" "[Am]\n" "[Am9]\n" "[F]\n" "[Am6]\n" "[A]\n" "[Aadd9], [Bm9]\n" "[Dbaug], [Faug]\n" "[Aaug]\n" "[A6], [Gbm]\n" "[Gbm6]\n" "[Asus4], [Dsus2]\n" "[Dm]\n" "[Dm6], [G9]\n" "[Dm7], [F6]\n" "[D]\n" "[Bm7], [D6]\n" "[D7]\n" "[Dmaj7]\n" "[Gm9]\n" "[D7sus4]\n" "[F7]\n" "[Ebdim]\n" "[B7]\n" "[Adim], [Gbdim]\n" "[Cm6], [F9]\n" "[Fmaj7]\n" "[B7sus4]\n" "[D9]\n" "[Gbm7]\n" "[Bbsus2], [Fsus4]\n" "[Bbdim]\n" "[Bbm]\n" "[Bbm9]\n" "[Gb]\n" "[Bbm6]\n" "[Bbmaj7]\n" "[Bb]\n" "[Bbadd9]\n" "[Bbaug], [Daug], [Gbaug]\n" "[Bb9]\n" "[Bbsus4]\n" "[Ebm]\n" "[Ab9], [Ebm6]\n" "[Ebm7], [Gb6]\n" "[Cm7], [Eb6]\n" "[Eb7]\n" "[Abadd9]\n" "[Ebsus2]\n" "[Gb7]\n" "[Bsus2], [Gbsus4]\n" "[Bdim]\n" "[Bm]\n" "[Bmaj7]\n" "[B]\n" "[Badd9]\n" "[Baug]\n" "[Abm]\n" "[Bsus4], [Esus2]\n" "[E6]") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html