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

`
`
gmX

Test String

Code Generator

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"<td.*?class=\"namelinks\".*?\">(.+?)</a>" test_str = ("<tr>\n" " <td class=\"field_domain\"><a href=\"/goto/1/eboo74/2/\" target=\"_blank\" title=\"advocaciamdc.com\" class=\"namelinks\" id=\"linksdd-domaineboo74\">advocaciamdc.com</a><ul id=\"links-domaineboo74\" class=\"kmenucontent\" style=\"display:none;\"><li class=\"first\"><a href=\"/goto/16/eg4d59/2/\" target=\"_blank\" class=\"favicons favgodaddy\" title=\"Register at GoDaddy.com\">GoDaddy.com</a></li><li><a href=\"/goto/53/ee87fh/2/\" target=\"_blank\" class=\"favicons favdynadot\" title=\"Register at Dynadot.com\">Dynadot.com</a></li><li><a href=\"/goto/43/eecp19/2/\" target=\"_blank\" class=\"favicons favnamecheap\" title=\"Register at Namecheap.com\">Namecheap.com</a></li></ul></td>\n" " <td class=\"field_watchlist\"><span class=\"wl\" id=\"wl-2-eboo74\"></span></td>\n" " <td class=\"field_length\">12</td>\n" " <td class=\"field_bl\"><a href=\"/goto/34/ebdukr/2/\" target=\"_blank\" class=\"bllinks\" title=\"0\" id=\"backlinks-bleboo74\">0</a><ul id=\"links-bleboo74\" class=\"kmenucontent\" style=\"display:none;\"><li class=\"first\"><a href=\"/goto/34/ebdukr/2/\" target=\"_blank\" class=\"favicons favmajestic\" title=\"Check Backlinks on Majestic.com\">Majestic.com</a></li><li class=\"seperator\">&nbsp;</li><li><a href=\"/goto/28/eg64b8/2/\" target=\"_blank\" class=\"favicons favseokicks\" title=\"Check Backlinks on SEOkicks.de\">SEOkicks.de</a></li><li><a href=\"/goto/56/ed1td8/2/\" target=\"_blank\" class=\"favicons favsemrush\" title=\"Check Backlinks on SEMRush.com\">SEMRush.com</a></li><li><a href=\"/goto/27/ecwtfo/2/\" target=\"_blank\" class=\"favicons favsearchm\" title=\"Searchmetrics\">Searchmetrics</a></li></ul></td>\n" " <td class=\"field_domainpop\"><a href=\"/goto/28/eg64b8/2/\" target=\"_blank\" title=\"0\">0</a></td>\n" " <td class=\"field_creationdate\"><a href=\"/goto/8/edemrz/2/\" target=\"_blank\" title=\"Whois Creation Date: 2019-08-06\">2019</a></td>\n" " <td class=\"field_abirth\">-</td>\n" " <td class=\"field_aentries\"><a href=\"/goto/6/eddzzf/2/\" target=\"_blank\" title=\"0 saved crawl results\">0</a></td>\n" " <td class=\"field_alexa\"><a href=\"/goto/4/eddwsg/2/\" target=\"_blank\" title=\"0\" class=\"\">0</a></td>\n" " <td class=\"field_majestic_globalrank\"><a href=\"/goto/34/ebdukr/2/\" target=\"_blank\">0</a></td>\n" " <td class=\"field_dmoz\">-</td>\n" " <td class=\"field_statustld_registered\"><a href=\"/domain/advocaciamdc.com#namestatus\" target=\"_blank\">0</a></td>\n" " <td class=\"field_statuscom\"><a href=\"/goto/18/efli0j/2/?tld=com\" target=\"_blank\" class=\"sprite stlds stld22c\" title=\".com available\"><span>available</span></a></td>\n" " <td class=\"field_statusnet\"><a href=\"/goto/18/efli0j/2/?tld=net\" target=\"_blank\" class=\"sprite stlds stld22c\" title=\".net available\"><span>available</span></a></td>\n" " <td class=\"field_statusorg\"><a href=\"/goto/18/efli0j/2/?tld=org\" target=\"_blank\" class=\"sprite stlds stld22c\" title=\".org available\"><span>available</span></a></td>\n" " <td class=\"field_statusbiz\"><a href=\"/goto/18/efli0j/2/?tld=biz\" target=\"_blank\" class=\"sprite stlds stld22c\" title=\".biz available\"><span>available</span></a></td>\n" " <td class=\"field_statusinfo\"><a href=\"/goto/18/efli0j/2/?tld=info\" target=\"_blank\" class=\"sprite stlds stld22c\" title=\".info available\"><span>available</span></a></td>\n" " <td class=\"field_statusde\"><a href=\"/goto/18/efli0j/2/?tld=de\" target=\"_blank\" class=\"sprite stlds stld22c\" title=\".de available\"><span>available</span></a></td>\n" " <td class=\"field_adddate\">2020-10-25</td>\n" " <td class=\"field_related_cnobi\">-</td>\n" " <td class=\"field_wikipedia_links\">-</td>\n" " <td class=\"field_changes\">Yesterday 18:55</td>\n" " <td class=\"field_whois\"><a href=\"/goto/1/eboo74/2/\" target=\"_blank\" title=\"Register now\" class=\"status_free\">available</a></td>\n" " <td class=\"field_relatedlinks\"><a class=\"sprite sicon smenu domainlinks\" href=\"#\" id=\"expiredcom-eboo74\" title=\"Related Links (click here for menu)\"><span>RL</span></a><ul id=\"links-eboo74\" class=\"kmenucontent\" style=\"display:none;\"><li class=\"first\"><a href=\"/goto/16/eg4d59/2/\" target=\"_blank\" class=\"favicons favgodaddy\" title=\"Register at GoDaddy.com\">GoDaddy.com</a></li><li><a href=\"/goto/53/ee87fh/2/\" target=\"_blank\" class=\"favicons favdynadot\" title=\"Register at Dynadot.com\">Dynadot.com</a></li><li><a href=\"/goto/43/eecp19/2/\" target=\"_blank\" class=\"favicons favnamecheap\" title=\"Register at Namecheap.com\">Namecheap.com</a></li><li class=\"seperator\">&nbsp;</li><li><a href=\"/domain/advocaciamdc.com\" class=\"favicons favhomepage\" target=\"_blank\" title=\"Domain Details on ExpiredDomains.net\">Domain Details</a></li><li><a href=\"/goto/116/ebesj8/2/\" target=\"_blank\" class=\"favicons favgodaddy\" title=\"GoDaddy.com Appraisal\">GoDaddy Appraisal</a></li><li><a href=\"/goto/25/eep3go/2/\" target=\"_blank\" class=\"favicons favsemrush\" title=\"Check Rankings on SEMRush.com\">SEMRush</a></li><li><a href=\"/goto/93/eb1rfr/2/\" target=\"_blank\" class=\"favicons favtrademarkia\" title=\"Check Domain Name on Trademarkia\">Trademarkia</a></li><li><a href=\"/goto/7/ec5uh7/2/\" target=\"_blank\" class=\"favicons favgoogle\" title=\"Google the Domain Name\">Google Name</a></li><li><a href=\"/goto/11/eekeoy/2/\" target=\"_blank\" class=\"favicons favgoogle\" title=\"Google info:domain.tld\">Google Info</a></li><li><a href=\"/goto/15/ef6qyy/2/\" target=\"_blank\" class=\"favicons favgoogle\" title=\"Google site:domain.tld\">Google Site</a></li><li><a href=\"/goto/6/eddzzf/2/\" target=\"_blank\" class=\"favicons favarchiveorg\" title=\"Check Website in Wayback Machine\">Wayback Machine</a></li><li><a href=\"/goto/9/ebbfv1/2/\" target=\"_blank\" class=\"favicons favhomepage\" title=\"Visit the Website\">Visit Domain</a></li><li><a href=\"/goto/8/edemrz/2/\" target=\"_blank\" class=\"favicons favwhois\" title=\"Whois Domain\">Whois Domain</a></li><li><a href=\"/goto/21/ecqo3m/2/\" target=\"_blank\" class=\"favicons favdomaintools\" title=\"Check Domainhistory on Domaintools.com\">Domaintools.com</a></li></ul></td>\n" " </tr>") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.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