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

import re regex = re.compile(r"<recode>([^#]*?)<\/sumfa>", flags=re.MULTILINE | re.IGNORECASE) test_str = ("<item>\n" " <imd>\n" " <fs_ar>T</fs_ar>\n" " <fs_as>T</fs_as>\n" " <fs_af>T</fs_af>\n" " <fs_aic>T</fs_aic>\n" " <fs_air>T</fs_air>\n" " <kid>601</kid>\n" " </imd>\n" " <title>whatever</title>\n" " <recode>200</recode>\n" " <reto>312</reto>\n" " <doto>312</doto>\n" " <pathrela>whatever.html</pathrela>\n" " <realext>.php</realext>\n" " <kindext>.html</kindext>\n" " <charset>iso-8859-1</charset>\n" " <mime>text/html</mime>\n" " <sizeex>5633</sizeex>\n" " <sizeco>T</sizeco>\n" " <impsco>1.602941</impsco>\n" " <impscosca>1.455153</impscosca>\n" " <chgscosca>1.455153</chgscosca>\n" " <lkstae>1</lkstae>\n" " <lnkta>3</lnkta>\n" " <sumfa>1</sumfa>\n" " </item>\n" " <item>\n" " <imd>\n" " <fs_ar>T</fs_ar>\n" " <fs_as>T</fs_as>\n" " <fs_af>T</fs_af>\n" " <fs_aic>T</fs_aic>\n" " <fs_air>T</fs_air>\n" " <kid>23</kid>\n" " </imd>\n" " <title>Whats UP Dog</title>\n" " <recode>200</recode>\n" " <reto>219</reto>\n" " <doto>219</doto>\n" " <pathrela>wud.html</pathrela>\n" " <realext>.html</realext>\n" " <kindext>.html</kindext>\n" " <charset>iso-8859-1</charset>\n" " <mime>text/html</mime>\n" " <sizeex>6252</sizeex>\n" " <sizeco>T</sizeco>\n" " <lastmo>2013-04-18 08:51:58</lastmo>\n" " <impsco>398.818604</impsco>\n" " <impscosca>9.11296</impscosca>\n" " <chgscosca>8.657311</chgscosca>\n" " <lksta>2</lksta>\n" " <lkstae>8</lkstae>\n" " <lnkta>414</lnkta>\n" " <sumfa>1</sumfa>\n" " </item>") 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