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=\"(?<url>[^\"]*(?<=\?|&)o=(?<number>\d+)[^\"]*)\"[^>]*>\s*last", flags=re.MULTILINE | re.IGNORECASE | re.DOTALL) test_str = ("<div class=\"listing_thumbs_resultcontainer\">\n" " \n" " <span class=\"FloatLeft nav-next-btn\">\n" " \n" " \n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&amp;q=nike air&amp;th=1\" title=\"Go to first page\">« First</a>\n" " \n\n" " \n" " <span class=\"nav-next-btn nohistory marginLeft\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&amp;q=nike air&amp;th=1\" title=\"Go to previous page\">\n" " ‹ Previous\n" " </a>\n" " </span>\n" " &nbsp; \n" " \n" " \n\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=1&amp;q=nike air&amp;th=1\" title=\"Page 1 of 29\">1</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=2&amp;q=nike air&amp;th=1\" title=\"Page 2 of 29\">2</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=3&amp;q=nike air&amp;th=1\" title=\"Page 3 of 29\">3</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=4&amp;q=nike air&amp;th=1\" title=\"Page 4 of 29\">4</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=5&amp;q=nike air&amp;th=1\" title=\"Page 5 of 29\">5</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=6&amp;q=nike air&amp;th=1\" title=\"Page 6 of 29\">6</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=7&amp;q=nike air&amp;th=1\" title=\"Page 7 of 29\">7</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=8&amp;q=nike air&amp;th=1\" title=\"Page 8 of 29\">8</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=9&amp;q=nike air&amp;th=1\" title=\"Page 9 of 29\">9</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=10&amp;q=nike air&amp;th=1\" title=\"Page 10 of 29\">10</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=11&amp;q=nike air&amp;th=1\" title=\"Page 11 of 29\">11</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=12&amp;q=nike air&amp;th=1\" title=\"Page 12 of 29\">12</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=13&amp;q=nike air&amp;th=1\" title=\"Page 13 of 29\">13</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=14&amp;q=nike air&amp;th=1\" title=\"Page 14 of 29\">14</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=15&amp;q=nike air&amp;th=1\" title=\"Page 15 of 29\">15</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=16&amp;q=nike air&amp;th=1\" title=\"Page 16 of 29\">16</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=17&amp;q=nike air&amp;th=1\" title=\"Page 17 of 29\">17</a>\n" " </span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=18&amp;q=nike air&amp;th=1\" title=\"Page 18 of 29\">18</a>\n" " </span>\n" " \n" " <span class=\"nav-active\"><strong>19</strong></span>\n" " <span class=\"non-active nohistory\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&amp;q=nike air&amp;th=1\" title=\"Page 20 of 29\">20</a>\n" " </span\n" " \n" " \n" " </span>\n" " \n" " <span class=\"nav-next-btn nohistory FloatRight\">\n" " \n" " <span class=\"nav-next-btn nohistory marginRight\">\n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=20&amp;q=nike air&amp;th=1\" title=\"Go to next page\">\n" " Next ›\n" " </a>\n" " </span>\n" " \n" " \n" " \n" " \n" " <a href=\"http://www.mudah.my/Malaysia/nike+air-for-sale?o=29&amp;q=nike air&amp;th=1\" title=\"Go to last page\">\n" " Last »\n" " </a>\n" " \n" " \n" " </span> \n" " \n" " </div>") 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