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"<a href=\"javascript:void\(0\)\"[^>]*>(.*?)id=\"sw-slots-grid-line-break\"", flags=re.IGNORECASE | re.DOTALL) test_str = ("<div id=\"tmm-grid-swatch-HARDCOVER\" class=\"a-column a-span6 a-text-left swatchElement selected celwidget\" role=\"listitem\" data-csa-c-id=\"rqzqyx-arj8qg-jifnrc-pelgtz\" data-cel-widget=\"tmm-grid-swatch-HARDCOVER\"> <span class=\"a-button a-button-selected a-spacing-none a-button-toggle format\" id=\"a-autoid-2\"><span class=\"a-button-inner\"><a href=\"javascript:void(0)\" role=\"radio\" aria-checked=\"true\" aria-current=\"page\" class=\"a-button-text a-text-left\" id=\"a-autoid-2-announce\"> <span class=\"slot-title\">\n" " <span aria-label=\"Hardcover Format:\">Hardcover</span> <br> </span>\n" " <span class=\"slot-price\">\n" " <span aria-label=\"$16.94\" class=\"a-size-base a-color-price a-color-price\"> $16.94 </span> </span>\n" " <br id=\"sw-slots-grid-line-break\">\n\n" " </a></span></span> </div>") match = regex.search(test_str) if match: print(f"Match 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