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"(?:\n[\h]*@|^[\h]*@)\K([0-9]+)(?=[\s]*\n|[\s]*$)|(?<=[\h\n,]@)([0-9]+)(?=[\h\n,.-]|$)|(?<=[\s,]@|^@)\K([a-zA-ZæøåÆØÅ_0-9]*[a-zA-ZæøåÆØÅ_]+[a-zA-ZæøåÆØÅ_0-9]*+)(?=[\s,]|[-.,:]*[\s]|[-.,:]*$)") test_str = (" @ab.\n" "# ^ match at start of string\n\n\n" "# GROUP 1\n" "@0123456789\n" "@9412334\n" " @00000 \n" "@999\n" " @123\n" " @123\n\n" "# GROUP 2\n" ",@123\n" "@123,@123,@123\n" "asdasd,@4782,asdada\n" "@31, @2312, @1231\n" "@123 @123 @1234567890\n" "@123.-, \n" "@123.\n\n" "# GROUP 3\n" "@abdefghijklmnopqrstuæøå\n" "@ABCDEFGÆØÅ\n" "@123abc\n" "@abc123\n" "@123abc123\n" "@abc.\n" "@abc-\n" "@abc:\n\n" "# NO MATCH\n" "@\n" ".@412\n" "-@634\n" "@5234;\n" "@4234@\n" "@@1231\n" "test@example.com\n" "test@example\n" "@asd@asd\n" "asd@as-_d\n" "@asd.@asd.@asd\n" "@asd-d \n" "@ads.com\n" "@ads-_\n" "@asd^\n" "@asdf\n\n" "Loreæøåm ipasdæøåsumæø dolor sit amet, consectetur adipisicing elit, sed do eiusmod @1234567890 @1 @0 tempor incididunt ut labore @1æøåÆØÅ123et0 dolore magna aliqua. Ut enim ad minim @veniam, @quis @nostrud @123 exercitation ullamco laboris nisi ut aliquip ex ea @commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit æøå esse cillum dolore @asd,@asd,@asd eu fugiat nulla test@example.com pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. \n\n\n" "# v Match at end of string\n" "@ab.") 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