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

/
/
g

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /https?\:\/\/(www.)?([a-z\.A-Z\-]+)\/.*/ str = 'https://thenextweb.com/dd/2014/04/08/ux-designers-side-drawer-navigation-costing-half-user-engagement/ https://developer.android.com/training/implementing-navigation/nav-drawer.html http://www.viralandroid.com/2015/09/android-sliding-menu-with-webview.html https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&cad=rja&uac…Android&usg=AFQjCNFRk6d5AhBfonGM106Sad2tjoBT7g&sig2=kiMOjbXGWDcWRLpLOvyYQQ https://github.com/twbs/bootstrap/issues/4550 https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uac…ypes%2F&usg=AFQjCNHRDjZYkePYfSuVIkV9e4XLWM0V_g&sig2=_jN849JNw4Zbp2s3Anlzgw http://stackoverflow.com/questions/24463890/open-webview-when-item-in-the-side-slide-menu-is-clicked https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&cad=rja&uac…s-popup&usg=AFQjCNFtDDELoRlF3_9SuoyJJ2kzZsDrDw&sig2=54H1u1WQd2NG0aywd6G4SQ https://support.proto.io/hc/en-us/community/posts/207856878-Sliding-sidebar-menu-s-links-do-not-work-on-Android-app https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=10&cad=rja&ua…b265b49&usg=AFQjCNEgo2JyzndfiLfH9duieqVd71CsVA&sig2=txF-3ZgdzHydpJJJ2BwT5Q https://developer.chrome.com/multidevice/android/customtabs http://www.howtogeek.com/237951/how-to-add-website-links-to-the-windows-10-start-menu/ https://paul.kinlan.me/deep-app-linking-on-android-and-chrome/ https://developers.google.com/apps-script/guides/dialogs https://material.io/guidelines/patterns/navigation-drawer.html https://help.shopify.com/manual/sell-online/online-store/menus-and-links https://books.google.com/books?id=IAVnDQAAQBAJ&pg=PT129&lpg=PT129&dq=androi…PsnBph0QJXDzjUY&hl=en&sa=X&ved=0ahUKEwi5_6G-9pXSAhXHurwKHc6RCQEQ6AEIgwEwEA https://lmjabreu.com/post/why-and-how-to-avoid-hamburger-menus http://stacktips.com/tutorials/android/navigation-drawer-android-example https://www.npmjs.com/package/cordova-universal-links-plugin https://support.wunderlist.com/customer/portal/articles/1767713 https://www.thepolyglotdeveloper.com/2014/12/open-dynamic-links-using-cordova-inappbrowser/ http://www.infoworld.com/article/2610416/web-browsers/web-browsers-50-tips-and-tricks-for-chrome-power-users.html https://vivaldi.com/?lang=en_US http://www.androidpolice.com/2016/01/20/google-android-app-can-now-open-links-in-chrome-custom-tabs-after-latest-update/ https://forum.ionicframework.com/t/external-links-in-side-menu-not-working/58384 http://dolphin.com/dolphin-for-android-phone-faqs/ https://www.facebook.com/business/help/312169205649942 http://blog.teamtreehouse.com/add-navigation-drawer-android http://forums.androidcentral.com/android-apps/593611-how-force-android-open-facebook-links-facebook-app.html https://plaid.com/docs/quickstart/ https://motorola-global-portal.custhelp.com/app/answers/prod_answer_detail/a_id/109551/p/30,6720,9583 http://blog.ionic.io/deeplinking-in-ionic-apps/ https://help.evernote.com/hc/en-us/articles/209004637-How-to-create-shortcuts-for-frequently-accessed-notes-notebooks-and-searches http://www.jqueryscript.net/tags.php?/side%20menu/ https://community.box.com/t5/Account-Information/How-To-Disable-Plugins-Add-Ons-Extensions-In-Multiple-Browsers/ta-p/19 https://support.mozilla.org/en-US/kb/using-tabs-firefox-android http://semantic-ui.com/modules/sidebar.html https://docs.citrix.com/en-us/xenmobile-apps/10/secure-web.html https://www.cnet.com/how-to/how-to-request-desktop-version-of-a-web-site-in-chrome-for-android/ http://mmenu.frebsite.nl/ http://tiddlywiki.com/ http://callmenick.com/post/slide-and-push-menus-with-css3-transitions https://www.lullabot.com/articles/navigation-and-deep-linking-with-react-native http://www.computerworld.com/article/2474114/android/4-hidden-settings-to-make-chrome-for-android-even-better.html http://help.tune.com/marketing-console/creating-and-using-deeplink-urls/ https://codepen.io/zavoloklom/pen/dIgco https://www.smashingmagazine.com/2012/06/responsive-menus-enhancing-navigation-on-mobile-websites/ https://get.slack.help/hc/en-us/articles/205166337-Customize-your-Slack-theme https://code.tutsplus.com/tutorials/mobile-web-quick-tip-phone-number-links--mobile-7667' subst = '$2' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html