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

/
/
gm

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 = "<p><span class='label'>Rating<\\/span>: <div class='metadata' id='rating'>(.*?)<\\/div><p>"; final String string = "<p><span class='label'>Adapter_Classes</span>: <div class='metadata list' id='adapter_classes'><ul>\n" + "<li>FanFictionNetSiteAdapter</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Author</span>: <div class='metadata list' id='author'><ul>\n" + "<li>Ms Katonic</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Authorhtml</span>: <div class='metadata' id='authorHTML'><a class='authorlink' href='https://www.fanfiction.net/u/27687/Ms-Katonic'>Ms Katonic</a></div><p>\n\n" + "<p><span class='label'>Author ID</span>: <div class='metadata list' id='authorId'><ul>\n" + "<li>27687</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Author URL</span>: <div class='metadata list' id='authorUrl'><ul>\n" + "<li>https://www.fanfiction.net/u/27687/Ms-Katonic</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Category</span>: <div class='metadata list' id='category'><ul>\n" + "<li>Elder Scroll series</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Characters</span>: <div class='metadata list' id='characters'><ul>\n" + "<li>Elisif</li>\n" + "<li>Argis the Bulwark</li>\n" + "<li>Madanach</li>\n" + "<li>Ulfric Stormcloak</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Packaged</span>: <div class='metadata datetime' id='dateCreated'>2020-11-26T00:15:59.499793</div><p>\n\n" + "<p><span class='label'>Published</span>: <div class='metadata datetime' id='datePublished'>2013-09-28T12:26:48</div><p>\n\n" + "<p><span class='label'>Updated</span>: <div class='metadata datetime' id='dateUpdated'>2015-05-05T18:23:45</div><p>\n\n" + "<p><span class='label'>Summary</span>: <div class='metadata' id='description'>Dragons may signify the world's end but as far as Elisif's concerned, her world ended well before that when Ulfric Stormcloak murdered her husband. So it is that no one's more surprised than her when a dragon attack on Solitude reveals that there's more to the High Queen in waiting than anyone</div><p>\n\n" + "<p><span class='label'>Extra Tags</span>: <div class='metadata list' id='extratags'><ul>\n" + "<li>FanFiction</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Favs</span>: <div class='metadata' id='favs'>343</div><p>\n\n" + "<p><span class='label'>Follows</span>: <div class='metadata' id='follows'>245</div><p>\n\n" + "<p><span class='label'>File Extension</span>: <div class='metadata' id='formatext'>.epub</div><p>\n\n" + "<p><span class='label'>File Format</span>: <div class='metadata' id='formatname'>epub</div><p>\n\n" + "<p><span class='label'>Genre</span>: <div class='metadata list' id='genre'><ul>\n" + "<li>Adventure</li>\n" + "<li>Drama</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Langcode</span>: <div class='metadata' id='langcode'>en</div><p>\n\n" + "<p><span class='label'>Language</span>: <div class='metadata' id='language'>English</div><p>\n\n" + "<p><span class='label'>Lastupdate</span>: <div class='metadata list' id='lastupdate'><ul>\n" + "<li>Last Update Year/Month: 2015/05</li>\n" + "<li>Last Update: 2015/05/05</li>\n" + "</ul></div><p>\n\n" + "<p><span class='label'>Chapters</span>: <div class='metadata int' id='numChapters'>50</div><p>\n\n" + "<p><span class='label'>Words</span>: <div class='metadata' id='numWords'>383,344</div><p>\n\n" + "<p><span class='label'>Python_Version</span>: <div class='metadata' id='python_version'>3.8.5 (default, Aug 26 2020, 22:00:02) [MSC v.1927 64 bit (AMD64)]</div><p>\n\n" + "<p><span class='label'>Rating</span>: <div class='metadata' id='rating'>M</div><p>\n\n" + "<p><span class='label'>Reviews</span>: <div class='metadata' id='reviews'>203</div><p>\n\n" + "<p><span class='label'>Story URL Section</span>: <div class='metadata' id='sectionUrl'>https://www.fanfiction.net/s/9721808/1/</div><p>\n\n" + "<p><span class='label'>Publisher</span>: <div class='metadata' id='site'>www.fanfiction.net</div><p>\n\n" + "<p><span class='label'>Site Abbrev</span>: <div class='metadata' id='siteabbrev'>ffnet</div><p>\n\n" + "<p><span class='label'>Status</span>: <div class='metadata' id='status'>Completed</div><p>\n\n" + "<p><span class='label'>Story ID</span>: <div class='metadata' id='storyId'>9721808</div><p>\n\n" + "<p><span class='label'>Story URL</span>: <div class='metadata' id='storyUrl'>https://www.fanfiction.net/s/9721808/1/</div><p>\n\n" + "<p><span class='label'>Title</span>: <div class='metadata' id='title'>The Wolf Queen Awakens</div><p>\n\n" + "<p><span class='label'>Titlehtml</span>: <div class='metadata' id='titleHTML'><a class='titlelink' href='https://www.fanfiction.net/s/9721808/1/'>The Wolf Queen Awakens</a></div><p>\n\n" + "<p><span class='label'>Downloader Version</span>: <div class='metadata' id='version'>FanFicFare v3.99.18</div><p>"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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