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

r"
"
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"\d{3}-\d{4}" test_str = ("[Verse 1]\n" "Jenny, Jenny, who can I turn to?\n" "You give me somethin' I can hold on to\n" "I know you think I'm like the others before\n" "Who saw your name and number on the wall\n\n" "[Chorus 1]\n" "Jenny, I got your number\n" "I need to make you mine\n" "Jenny, don't change your number\n\n" "[Post-Chorus]\n" "867-5309\n" "867-5309\n" "867-5309\n" "867-5309\n\n" "[Verse 2]\n" "Jenny, Jenny, you're the girl for me\n" "Oh, you don't know me, but you make me so happy\n" "I tried to call you before, but I lost my nerve\n" "I tried my imagination, but I was disturbed\n\n" "[Chorus 1]\n" "Jenny, I got your number\n" "I need to make you mine\n" "Jenny, don't change your number\n\n" "[Post-Chorus]\n" "867-5309\n" "867-5309\n" "867-5309\n" "867-5309\n\n" "[Bridge]\n" "I got it, (I got it), I got it\n" "I got your number on the wall\n" "I got it, (I got it), I got it\n" "For a good time, for a good time call\n\n" "[Chorus 2]\n" "Jenny, don't change your number\n" "I need to make you mine\n" "Jenny, I call your number\n\n" "[Post-Chorus]\n" "867-5309\n" "867-5309\n" "867-5309\n" "867-5309\n\n" "[Breakdown]\n" "Jenny, Jenny, who can I turn to?\n" "867-5309\n" "For the price of a dime I can always turn to you\n" "867-5309\n\n" "[Outro]\n" "867-5309\n" "867-5309\n" "867-5309\n" "867-5309\n" "5309\n" "867-5309 (5309)\n" "867-5309 (5309)\n" "867-5309") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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