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"\[(\[?)(?P<shortcodename>\w\S+)(?![/w-])([^\]\/]*(?:\/(?!\])[^\]\/]*)*?)(?:(\/)\]|\](?:([^\[]*(?:\[(?!\/\2\])[^\[]*)*)\[\/\2\])?)(\[?)") test_str = ("\n" "[openandclose src=\"1234\" id=\"abc\"]some content[/openandclose]\n\n" "[openwithattrs src=\"1234\" id=\"abc\"] \n\n" "[mmbox_with-attrs title=\"TOOL: Track Your Net Worth - Personal Capital\" link=\"https://go.millennialmoney.com/personal-capital/\" image=\"https://millennialmoney.com/wp-content/uploads/2020/05/personal-capital-square.jpg\" ctatext=\"Get Started!\" desc=\"With Personal Capital, you can see your net worth, analyze investments, and discover any hidden fees you weren&#8217;t aware of before &#8211; as well as set spending and saving goals.\" price=\"FREE\" color=\"#32C4F3\"]\n\n" "[HL_QUOTER]\n\n" "[open_only-]\n\n" "[mmtoplist_ma type=\"Auto\" max=\"2\" header=\"0\"]\n\n" "[tmf_investnow500 source=\"isammtxt0000006\" header=\"Where to invest $1000 right now\" aside=\"Even More Stock Picks\" link=\"https://www.fool.com/order/fe_offers/wf/602d8976-8f2f-41c3-9ddf-1ab6c2b5ba06?c=sa-inv-btr&amp;amp;utm_campaign=topmillennialtrends&amp;amp;utm_medium=ecap_widget&amp;amp;utm_source=millennialmoney&amp;amp;campaign=sa-bbn-evergreen\"]\n\n" "[earningPotential amount=\"$50,371\" timeframe=\"yr\"] [earningPotential]") 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