Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
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
No Match

r"
"
x

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r""" <div\sclass="row">\s<div\sclass="col-xs-12">\s<div\sclass="all_seasons">\s<div\sclass="episodes_left\scol-xs-6\spull-left">\s((.|\n)*)<br>(?:(</div>|\s)*?) """ test_str = ("<div class=\"row\">\n" "<div class=\"col-xs-12\">\n" "<div class=\"all_seasons\">\n" "<div class=\"episodes_left col-xs-6 pull-left\">\n" "<a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e32'>Last Week Tonight With John Oliver S02E32 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e31'>Last Week Tonight With John Oliver S02E31 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e30'>Last Week Tonight With John Oliver S02E30 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e29'>Last Week Tonight With John Oliver S02E29 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e28'>Last Week Tonight With John Oliver S02E28 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e27'>Last Week Tonight With John Oliver S02E27 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e25-church'>Last Week Tonight With John Oliver S02E25 &#8211; Church </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e24-season-2-episode-24'>Last Week Tonight With John Oliver S02E24 &#8211; Season 2, Episode 24 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e23-season-2-episode-23'>Last Week Tonight With John Oliver S02E23 &#8211; Season 2, Episode 23 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e23-season-2-episode-23-720p'>Last Week Tonight With John Oliver S02E23 &#8211; Season 2, Episode 23 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e22-season-2-episode-22-720p'>Last Week Tonight With John Oliver S02E22 &#8211; Season 2, Episode 22 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e22-season-2-episode-22'>Last Week Tonight With John Oliver S02E22 &#8211; Season 2, Episode 22 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e21-season-2-episode-21'>Last Week Tonight With John Oliver S02E21 &#8211; Season 2, Episode 21 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e21-season-2-episode-21-720p'>Last Week Tonight With John Oliver S02E21 &#8211; Season 2, Episode 21 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e20-season-2-episode-20'>Last Week Tonight With John Oliver S02E20 &#8211; Season 2, Episode 20 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e20-season-2-episode-20-720p'>Last Week Tonight With John Oliver S02E20 &#8211; Season 2, Episode 20 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e19-season-2-episode-19-720p'>Last Week Tonight With John Oliver S02E19 &#8211; Season 2, Episode 19 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e19-season-2-episode-19'>Last Week Tonight With John Oliver S02E19 &#8211; Season 2, Episode 19 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e18-season-2-episode-18-720p'>Last Week Tonight With John Oliver S02E18 &#8211; Season 2, Episode 18 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e18-season-2-episode-18'>Last Week Tonight With John Oliver S02E18 &#8211; Season 2, Episode 18 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e17-season-2-episode-17'>Last Week Tonight With John Oliver S02E17 &#8211; Season 2, Episode 17 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e17-season-2-episode-17-720p'>Last Week Tonight With John Oliver S02E17 &#8211; Season 2, Episode 17 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e16-season-2-episode-16'>Last Week Tonight With John Oliver S02E16 &#8211; Season 2, Episode 16 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e16-season-2-episode-16-720p'>Last Week Tonight With John Oliver S02E16 &#8211; Season 2, Episode 16 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e15-season-2-episode-15'>Last Week Tonight With John Oliver S02E15 &#8211; Season 2, Episode 15 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e15-season-2-episode-15-720p'>Last Week Tonight With John Oliver S02E15 &#8211; Season 2, Episode 15 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e14-season-2-episode-14'>Last Week Tonight With John Oliver S02E14 &#8211; Season 2, Episode 14 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e13-season-2-episode-13'>Last Week Tonight With John Oliver S02E13 &#8211; Season 2, Episode 13 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e13-season-2-episode-13-720p'>Last Week Tonight With John Oliver S02E13 &#8211; Season 2, Episode 13 720p </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e12-season-2-episode-12'>Last Week Tonight With John Oliver S02E12 &#8211; Season 2, Episode 12 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e11-season-2-episode-11'>Last Week Tonight With John Oliver S02E11 &#8211; Season 2, Episode 11 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e10-season-2-episode-10'>Last Week Tonight With John Oliver S02E10 &#8211; Season 2, Episode 10 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e09-season-2-episode-9'>Last Week Tonight With John Oliver S02E09 &#8211; Season 2, Episode 9 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e08-season-2-episode-8'>Last Week Tonight With John Oliver S02E08 &#8211; Season 2, Episode 8 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e07-season-2-episode-7'>Last Week Tonight With John Oliver S02E07 &#8211; Season 2, Episode 7 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e05-season-2-episode-5'>Last Week Tonight With John Oliver S02E05 &#8211; Season 2, Episode 5 </a>\n" "<br></div><div class='col-xs-6 pull-right'> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e04-season-2-episode-4'>Last Week Tonight With John Oliver S02E04 &#8211; Season 2, Episode 4 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-with-john-oliver-s02e03-season-2-episode-3'>Last Week Tonight With John Oliver S02E03 &#8211; Season 2, Episode 3 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-john-oliver-s02e02-season-2-episode-2'>Last Week Tonight With John Oliver S02E02 &#8211; Season 2, Episode 2 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-john-oliver-s02e01-season-2-episode-1'>Last Week Tonight With John Oliver S02E01 &#8211; Season 2, Episode 1 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-john-oliver-s01e24'>Last Week Tonight With John Oliver S01E24 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-john-oliver-s01e23'>Last Week Tonight With John Oliver S01E23 </a>\n" "<br> <a href='http://watchseries-online.li/episode/last-week-tonight-john-oliver-s01e22'>Last Week Tonight With John Oliver S01E22 </a>\n" "<br> <a href='http://watchseries-online.li/2014/10/last-week-tonight-with-john-oliver-s01e21'>Last Week Tonight With John Oliver S01E21 </a>\n" "<br> <a href='http://watchseries-online.li/2014/10/last-week-tonight-with-john-oliver-s01e20'>Last Week Tonight With John Oliver S01E20 </a>\n" "<br> <a href='http://watchseries-online.li/2014/09/last-week-tonight-with-john-oliver-s01e19'>Last Week Tonight With John Oliver S01E19 </a>\n" "<br> <a href='http://watchseries-online.li/2014/09/last-week-tonight-with-john-oliver-s01e18'>Last Week Tonight With John Oliver S01E18 </a>\n" "<br> <a href='http://watchseries-online.li/2014/09/last-week-tonight-with-john-oliver-s01e17'>Last Week Tonight With John Oliver S01E17 </a>\n" "<br> <a href='http://watchseries-online.li/2014/09/last-week-tonight-with-john-oliver-s01e16'>Last Week Tonight With John Oliver S01E16 </a>\n" "<br> <a href='http://watchseries-online.li/2014/08/last-week-tonight-with-john-oliver-s01e15'>Last Week Tonight With John Oliver S01E15 </a>\n" "<br> <a href='http://watchseries-online.li/2014/08/last-week-tonight-with-john-oliver-2014-08-10'>Last Week Tonight With John Oliver (2014 08 10) </a>\n" "<br> <a href='http://watchseries-online.li/2014/08/last-week-tonight-with-john-oliver-s01e13'>Last Week Tonight With John Oliver S01E13 </a>\n" "<br> <a href='http://watchseries-online.li/2014/07/last-week-tonight-with-john-oliver-2014-07-27'>Last Week Tonight With John Oliver (2014 07 27) </a>\n" "<br> <a href='http://watchseries-online.li/2014/07/last-week-tonight-with-john-oliver-2014-07-27-readnfo'>Last Week Tonight With John Oliver (2014 07 27) Readnfo </a>\n" "<br> <a href='http://watchseries-online.li/2014/07/last-week-tonight-with-john-oliver-s01e11'>Last Week Tonight With John Oliver S01E11 </a>\n" "<br> <a href='http://watchseries-online.li/2014/07/last-week-tonight-with-john-oliver-s01e10'>Last Week Tonight With John Oliver S01E10 </a>\n" "<br> <a href='http://watchseries-online.li/2014/06/last-week-tonight-with-john-oliver-s01e09'>Last Week Tonight With John Oliver S01E09 </a>\n" "<br> <a href='http://watchseries-online.li/2014/06/last-week-tonight-with-john-oliver-s01e08'>Last Week Tonight With John Oliver S01E08 </a>\n" "<br> <a href='http://watchseries-online.li/2014/06/last-week-tonight-with-john-oliver-s01e07'>Last Week Tonight With John Oliver S01E07 </a>\n" "<br> <a href='http://watchseries-online.li/2014/06/last-week-tonight-with-john-oliver-s01e06-real-wso-ch'>Last Week Tonight With John Oliver S01E06 Real wso-ch </a>\n" "<br> <a href='http://watchseries-online.li/2014/06/last-week-tonight-with-john-oliver-s01e06'>Last Week Tonight With John Oliver S01E06 </a>\n" "<br> <a href='http://watchseries-online.li/2014/05/last-week-tonight-with-john-oliver-2014-05-18-repack'>Last Week Tonight With John Oliver (2014 05 18) Repack </a>\n" "<br> <a href='http://watchseries-online.li/2014/05/last-week-tonight-with-john-oliver-2014-05-18'>Last Week Tonight With John Oliver (2014 05 18) </a>\n" "<br> <a href='http://watchseries-online.li/2014/05/last-week-tonight-with-john-oliver-2014-05-11-2'>Last Week Tonight With John Oliver (2014 05 11) </a>\n" "<br> <a href='http://watchseries-online.li/2014/05/last-week-tonight-with-john-oliver-2014-05-11'>Last Week Tonight With John Oliver (2014 05 11) </a>\n" "<br> <a href='http://watchseries-online.li/2014/05/last-week-tonight-with-john-oliver-s01e02'>Last Week Tonight With John Oliver S01E02 </a>\n" "<br> <a href='http://watchseries-online.li/2014/04/last-week-tonight-with-john-oliver-s01e01'>Last Week Tonight With John Oliver S01E01 </a>\n" "<br> </div>\n" "</div>\n" "</div>\n" "</div> \n" "</div> \n" "</div>") matches = re.search(regex, test_str, re.VERBOSE) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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