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"((https?)?([^\/])*)", flags=re.IGNORECASE) test_str = ("http://www.christianliferesources.com/links.html\n" "google.com\n" "http://dhhs.ne.gov/publichealth/Pages/hew_hpe_nebraskacares_resources.aspx\n" "http://www.babysittersguide.mobi/resources/links.php\n" "http://www.lifeslittletreasures.org.au/prematurity/useful-links/\n" "http://www.rms.org.uk/outreach/index/WebLinks\n" "http://www.cellbiolabs.com/links-resources\n" "http://nationalcmlsociety.org/resources/cml-and-leukemia-links\n" "http://lifeslittletreasures.org.au/prematurity/useful-links/\n" "https://www.aps-spr.org/resources/helpful-links.asp\n" "http://www.womeningovernment.org/oncology/hpv/resources/online\n" "http://www.lymphoma.ca/lymphoma/resources/helpful-links\n" "http://www.nationalcmlsociety.org/resources/cml-and-leukemia-links\n" "https://www.lymphoma.ca/lymphoma/resources/helpful-links\n" "http://www.cyagen.com/us/en/resources/useful-links.html\n" "http://womeningovernment.org/oncology/hpv/resources/online\n" "http://www.citykinder.com/for-parents-to-be/links-we-like/\n" "https://www.womeningovernment.org/oncology/hpv/resources/online\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=89\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272\n" "http://www.christianliferesources.com/links.html?print=1\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=88\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=88\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=88\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=268\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=263\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=268\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=266\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=90\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=86\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=263\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=94\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=94\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=86\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=265\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=85\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=263\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=266\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=264\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=87\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=91\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=92\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=91\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=87\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=263\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=94\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=94\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=86\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=267\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=264\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=265\n" "http://www.transfusionmedicine.ca/resources/links/Web-Links\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=264\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=93\n" "http://www.easierparenting.com.au/resources/useful-links/\n" "http://www.swedishamerican.org/services/cancer_care/links/\n" "http://chd.org/adult-services/community-based-programs/cancer-house-hope/helpful-linksresources/\n" "http://www.aps-spr.org/resources/helpful-links.asp\n" "http://www.cyagen.com/us/ja/resources/useful-links.html\n" "https://www.transfusionmedicine.ca/resources/links/Web-Links\n" "http://www.communityoptions.ab.ca/resources/helpful-links\n" "https://www.lifeslittletreasures.org.au/prematurity-resources/useful-links/\n" "http://www.lifeslittletreasures.org.au/prematurity-resources/useful-links/\n" "https://www.rmhca.org/family-resources/helpful-links-for-families/\n" "http://lifeslittletreasures.org.au/prematurity-resources/useful-links/\n" "http://www.americantransplantfoundation.org/about-transplant/resources-and-links/other-organizations/\n" "http://perinatalresources.org/medical-education-links/\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=268\n" "http://www.losninos.com/resources/helpful-links/\n" "http://swedishamerican.org/services/cancer_care/links/\n" "http://fitwise.com.au/patient-resources/links-page\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=87\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=91\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=90\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=91\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=89\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=266\n" "http://tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=93\n" "http://tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=88\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=90\n" "http://www.tipslimited.co.uk/index.php?option=com_weblinks&view=weblink&id=272&Itemid=93\n" "http://www.hospicegiving.org/resources-links\n" "http://www.transfusionmedicine.ca/resources/links/web-links/itranfuse-australian-red-cross-blood-service\n" "http://tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks\n" "http://www.tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks\n" "http://tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=85\n" "http://tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=90\n" "http://www.tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=92\n" "http://www.tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=87\n" "http://tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=84\n" "http://www.tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=84\n" "http://www.tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=267\n" "http://tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=81\n" "http://www.tipslimited.co.uk/index.php?view=weblink&catid=93%3Acord-blood-banking&id=272%3Acordbloodbankingcom&option=com_weblinks&Itemid=81\n" "http://www.choicespregnancypartners.org/national-affiliates\n" "https://www.choicespregnancypartners.org/national-affiliates\n" "http://www.transfusionmedicine.ca/resources/links/web-links/cord-blood-center\n" "https://www.transfusionmedicine.ca/resources/links/web-links/cord-blood-center\n" "http://advantacare.net/Resource-Center/Medical-Web-Sites\n" "http://www.ncpeid.org/index.php/links-resources\n" "http://www.transfusionmedicine.ca/fr/resources/links/Web-Links\n" "https://www.transfusionmedicine.ca/fr/resources/links/Web-Links\n" "http://www.idahoperinatal.org/links.php\n" "http://www.transfusionmedicine.ca/resources/links/web-links/american-association-blood-banks-aabb\n" "https://www.transfusionmedicine.ca/fr/resources/links/web-links/itranfuse-australian-red-cross-blood-service\n" "http://ncpeid.org/index.php/links-resources/for-parents\n" "http://www.transfusionmedicine.ca/fr/resources/links/web-links/american-association-blood-banks-aabb\n" "http://www.transfusionmedicine.ca/fr/resources/links/web-links/itranfuse-australian-red-cross-blood-service\n" "https://www.transfusionmedicine.ca/resources/links/web-links/itranfuse-australian-red-cross-blood-service\n" "http://ncpeid.org/index.php/links-resources\n" "http://idahoperinatal.org/links.php\n" "http://www.soulchoice.org/links.html\n" "http://www.soulchoice.org/online-resources-and-helpful-links.html\n" "http://www.horsepowerforlife.org/resources/useful-links/\n" "http://www.fertilityresourceshouston.com/additional-information/helpful-links.aspx\n" "http://www.horsepowerforlife.org/index.php/resources/useful-links/\n" "http://www.sri-online.org/links/educational-resources\n" "http://www.rmhca.org/family-resources/helpful-links-for-families/\n" "https://perinatalresources.org/medical-education-links/\n" "http://aohna.org/resources-links/ohn-resources\n" "http://ichpcolorado.com/services/Links_to_National_Health_Care_Resources.htm\n" "http://www.healthystartbfg.com/Resources-Links.aspx\n" "http://healthystartbfg.com/Resources-Links.aspx\n" "http://www.ichpcolorado.com/services/Links_to_National_Health_Care_Resources.htm\n" "http://tkeckle.net/links/medical.html\n" "http://leavenfortheloaf.com/links/crisis-pregnancy-resources-in-nh/comment-page-1/#comments\n" "http://leavenfortheloaf.com/links/crisis-pregnancy-resources-in-nh/\n" "http://www.fitwise.com.au/patient-resources/links-page\n" "http://www.parentingmatters-epc.org/parent-resources-support/helpful-links/\n" "http://www.lifeslittletreasures.com.au/prematurity/useful-links/\n" "http://leukodystrophyresourceresearch.org/resources-news/useful-links/\n" "http://www.centralvalleymedicalcenter.com/resources/helpful-links\n" "https://www.achancetogrowfilm.com/resources/resource-links/\n" "http://wallofcourage.com/links/index.htm\n" "http://www.wallofcourage.com/links/index.htm\n" "http://myoc3.org/directory/catalog/companies/293?task=companies.showCompanyWebsite\n" "http://www.myoc3.org/component/jbusinessdirectory/companies/293?task=companies.showCompanyWebsite\n" "http://myoc3.org/component/jbusinessdirectory/companies/293?task=companies.showCompanyWebsite\n" "http://www.arearlylearning.org/index.php/parents/parent-links/12\n" "http://www.designedtobirth.com/links-books-and-resources.html\n" "http://www.myoc3.org/directory/catalog/companies/293?task=companies.showCompanyWebsite\n" "http://frontrangeobgyn.com/resources/links/\n" "http://arearlylearning.org/index.php/parents/parent-links/12\n" "http://www.arearlylearning.org/index.php/parents/parent-links?task=weblink.go&id=12\n" "http://movingbeyondcancer.com.au/useful-links?task=weblink.go&id=14\n" "http://www.motherandbabymatters.com/resources.html\n" "http://arearlylearning.org/index.php/parents/parent-links?task=weblink.go&id=12\n" "http://au.sascentre.com/resources/1323\n" "http://int.sascentre.com/resources/1323\n" "http://uk.sascentre.com/resources/1323\n" "http://www.koruselfdevelopment.com/index.php/links/16\n" "http://koruselfdevelopment.com/index.php/links/16\n" "http://msoncologysociety.org/links-resources.php\n" "http://www.msoncologysociety.org/links-resources.php\n" "http://www.lifeslittletreasures.com.au/prematurity-resources/useful-links/\n" "http://momchd.com/parenting-links-and-resources/\n" "http://flintobgyn.com/patient-resources/links/\n" "http://www.oxfordobgyninc.com/resources/related-links\n" "http://livehealthysiouxland.org/web-links/8-prevention/73-cord-blood-banking.html\n" "http://www.livehealthysiouxland.org/web-links/8-prevention/73-cord-blood-banking.html\n" "http://getready4baby.com/links.html\n" "http://www.getready4baby.com/links.html\n" "http://jesperson.se/test1/magpierss/scripts/cache/43521fb1322467036d3b55ea1d37a921\n" "http://jesperson.se/test1/magpierss/scripts/cache/43521fb1322467036d3b55ea1d37a921\n") 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