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>(.*)<\/p>", flags=re.DOTALL) test_str = ("<?xml version=\"1.0\" encoding=\"utf-8\"?>\n" "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.1//EN\"\n" " \"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd\">\n\n" "<html xmlns=\"http://www.w3.org/1999/xhtml\" xml:lang=\"en\">\n" "<head>\n" "xxxx\n" " <meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\"/>\n" " <meta name=\"calibre:cover\" content=\"true\"/>\n" " <title>Cover</title>\n" " <style type=\"text/css\" title=\"override_css\">\n" " @page {padding: 0pt; margin:0pt}\n" " body { text-align: center; padding:0pt; margin: 0pt; }\n" " </style>\n" " </head>\n" " <body>\n" " <div>\n" " <svg xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" version=\"1.1\" width=\"100%\" height=\"100%\" viewBox=\"0 0 566 734\" preserveAspectRatio=\"none\">\n" "<p>\n" "1\n" "2\n" "3\n" "4\n" "5\n" "</p>\n\n" " <image width=\"566\" height=\"734\" xlink:href=\"../Images/cover.jpeg\"/>\n" "yyyy\n" " </svg>\n" " </div>\n" "</body>\n" "</html>") 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