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

/
/
g

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^\"(?:(?:[^\"]*)\")+?," test_str = "\"POLICE ARREST MAN ACCUSED\\r\\nOF MURDERING MISSING GIRL\\r\\n \\r\\nA New York man is in cust-\\r\\nody after he confessed to \\r\\nthe murder of a Sterling\\r\\ngirl who had been missing.\\r\\n \\r\\nJohn Ward of Palmyra was\\r\\npulled over on Snake\\r\\nMeadow Hill Road last\\r\\nnight after a state troop-\\r\\ner reported hearing a gun-\\r\\nshot. The officer thought\\r\\nit might be poachers.\\r\\n \\r\\nThe officer said Ward was\\r\\nacting \\\"nervous and\\r\\nsuspicious\\\" after being\\r\\npulled over. When quest-\\r\\nioned, Ward reportedly\\r\\nsaid \\\"I've killed her\\\".\\r\\nAccording to the police re-\\r\\nport, the officer called\\r\\nfor backup after Ward be-\\r\\ncame increasingly upset,\\r\\nsaying repeatedly that\\r\\nthere was \\\"a demon inside\\r\\nher\\\".\\r\\nWard was taken to Sterling\\r\\npolice headquarters for\\r\\nfurther questioning. Ward\\r\\nthen confessed to\\r\\nauthorities that he shot\\r\\nand killed Amy Martin, a\\r\\nseventeen year-old girl\\r\\nwho had been missing for\\r\\nnine days after escaping\\r\\nfrom a mental institution.\\r\\n \\r\\nAfter a brief search,\\r\\npolice located Amy's body\\r\\nin the woods near the now-\\r\\nabandoned Martin home. In\\r\\naddition to receiving a \\r\\ngunshot wound to the sto-\\r\\nmach, Amy showed injuries\\r\\nsuggesting that she had \\r\\nbeen thrown out of the \\r\\nsecond story window of\\r\\nthe house. An officer who\\r\\nhelped recover the body\\r\\ntold reporters that Amy's\\r\\nface had been \\\"mutilated\\r\\nin a very brutal manner\\\".\\r\\nWard was found dressed as\\r\\na priest when he was\\r\\npulled over. It is sus-\\r\\npected that he imperson-\\r\\nated a priest to gain his\\r\\nvictim's trust after\\r\\nCatholic authorities in\\r\\nRome confirmed that Ward\\r\\nwas not an ordained\\r\\nminister.\\r\\n \\r\\n(The rest of the article\\r\\nis missing.)\\r\\n\"," matches = re.finditer(regex, test_str) 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