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
No Match

r"
"
g

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "([a-z]+\\.){2,}[a-z]+"; final String string = "# 🧩 ReVanced Patches\n\n" + "Official patches by ReVanced\n\n" + "## 📜 List of available patches\n\n" + "### 📦 `com.twitter.android`\n" + "<details>\n\n" + "| 💊 Patch | 📜 Description | 🏹 Target Version |\n" + "|:--------:|:--------------:|:-----------------:|\n" + "| `timeline-ads` | Removes ads from the Twitter timeline. | all |\n" + "</details>\n\n" + "### 📦 `com.reddit.frontpage`\n" + "<details>\n\n" + "| 💊 Patch | 📜 Description | 🏹 Target Version |\n" + "|:--------:|:--------------:|:-----------------:|\n" + "| `general-reddit-ads` | Removes general ads from the Reddit frontpage and subreddits. | all |\n" + "</details>\n\n" + "### 📦 `com.garzotto.pflotsh.ecmwf_a`\n" + "<details>\n\n" + "| 💊 Patch | 📜 Description | 🏹 Target Version |\n" + "|:--------:|:--------------:|:-----------------:|\n" + "| `pflotsh-ecmwf-subscription-unlock` | Unlocks all subscription features. | 3.5.4 |\n" + "</details>\n\n" + "### 📦 `com.google.android.apps.youtube.music`\n" + "<details>\n\n" + "| 💊 Patch | 📜 Description | 🏹 Target Version |\n" + "|:--------:|:--------------:|:-----------------:|\n" + "| `minimized-playback-music` | Enables minimized playback on Kids music. | 5.17.51 |\n" + "| `tasteBuilder-remover` | Removes the \"Tell us which artists you like\" card from the home screen. | 5.16.51 |\n" + "| `hide-get-premium` | Removes all \"Get Premium\" evidences from the avatar menu. | 5.17.51 |\n" + "| `compact-header` | Hides the music category bar at the top of the homepage. | 5.16.51 |\n" + "| `upgrade-button-remover` | Removes the upgrade tab from the pivot bar. | 5.17.51 |\n" + "| `background-play` | Enables playing music in the background. | 5.17.51 |\n" + "| `music-microg-support` | Allows YouTube Music ReVanced to run without root and under a different package name. | 5.17.51 |\n" + "| `music-video-ads` | Removes ads in the music player. | 5.17.51 |\n" + "| `codecs-unlock` | Adds more audio codec options. The new audio codecs usually result in better audio quality. | 5.17.51 |\n" + "| `exclusive-audio-playback` | Enables the option to play music without video. | 5.17.51 |\n" + "</details>\n\n" + "### 📦 `de.dwd.warnapp`\n" + "<details>\n\n" + "| 💊 Patch | 📜 Description | 🏹 Target Version |\n" + "|:--------:|:--------------:|:-----------------:|\n" + "| `promo-code-unlock` | Disables the validation of promo code. Any code will work to unlock all features. | all |\n" + "</details>\n\n" + "### 📦 `com.ss.android.ugc.trill`\n" + "<details>\n\n" + "| 💊 Patch | 📜 Description | 🏹 Target Version |\n" + "|:--------:|:--------------:|:-----------------:|\n" + "| `tiktok-ads` | Removes ads from TikTok. | all |\n" + "</details>\n\n" + "### 📦 `com.google.android.youtube`\n" + "<details>\n\n" + "| 💊 Patch | 📜 Description | 🏹 Target Version |\n" + "|:--------:|:--------------:|:-----------------:|\n" + "| `swipe-controls` | Adds volume and brightness swipe controls. | 17.29.34 |\n" + "| `seekbar-tapping` | Enables tap-to-seek on the seekbar of the video player. | 17.29.34 |\n" + "| `minimized-playback` | Enables minimized and background playback. | 17.29.34 |\n" + "| `amoled` | Enables pure black theme. | 17.29.34 |\n" + "| `disable-create-button` | Hides the create button in the navigation bar. | 17.29.34 |\n" + "| `hide-cast-button` | Hides the cast button in the video player. | all |\n" + "| `return-youtube-dislike` | Shows the dislike count of videos using the Return YouTube Dislike API. | 17.29.34 |\n" + "| `hide-autoplay-button` | Hides the autoplay button in the video player. | 17.29.34 |\n" + "| `premium-heading` | Shows premium branding on the home screen. | all |\n" + "| `custom-branding` | Changes the YouTube launcher icon and name to your choice (defaults to ReVanced). | all |\n" + "| `disable-fullscreen-panels` | Disables video description and comments panel in fullscreen view. | 17.29.34 |\n" + "| `old-quality-layout` | Enables the original quality flyout menu. | 17.29.34 |\n" + "| `hide-shorts-button` | Hides the shorts button on the navigation bar. | 17.29.34 |\n" + "| `hide-watermark` | Hides creator's watermarks on videos. | 17.29.34 |\n" + "| `sponsorblock` | Integrate SponsorBlock. | 17.29.34 |\n" + "| `enable-wide-searchbar` | Replaces the search icon with a wide search bar. This will hide the YouTube logo when active. | 17.29.34 |\n" + "| `tablet-mini-player` | Enables the tablet mini player layout. | 17.29.34 |\n" + "| `custom-video-buffer` | Lets you change the buffers of videos. | 17.29.34 |\n" + "| `always-autorepeat` | Always repeats the playing video again. | 17.29.34 |\n" + "| `microg-support` | Allows YouTube ReVanced to run without root and under a different package name with Vanced MicroG | 17.29.34 |\n" + "| `settings` | Adds settings for ReVanced to YouTube. | all |\n" + "| `enable-debugging` | Enables app debugging by patching the manifest file. | all |\n" + "| `custom-playback-speed` | Adds more video playback speed options. | 17.29.34 |\n" + "| `hdr-auto-brightness` | Makes the brightness of HDR videos follow the system default. | 17.29.34 |\n" + "| `remember-video-quality` | Adds the ability to remember the video quality you chose in the video quality flyout. | 17.29.34 |\n" + "| `video-ads` | Removes ads in the video player. | 17.29.34 |\n" + "| `general-ads` | Removes general ads. | 17.29.34 |\n" + "| `hide-infocard-suggestions` | Hides infocards in videos. | 17.29.34 |\n" + "</details>\n\n\n"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html