Regular Expressions 101

Save & Share

  • Current Version: 11
  • Update Regex
    ctrl+⇧+s
  • Save new Regex
    ctrl+s
  • Add to Community Library

Flavor

  • PCRE2 (PHP)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java
  • .NET 7.0 (C#)
  • Rust
  • PCRE (Legacy)
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests
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
Processing...

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 = "<\\s*[a-z]*[^>]*>(.*?)<\\s*/\\s*[a-z]*>|<[\\w]*>(.*?)<[/\\w]*>"; final String string = "<body>\n\n" + "<div class=\"header\">\n" + " <h1>My Website</h1>\n" + " <p>A <b>responsive</b> website created by me.</p>\n" + "</div>\n\n" + "<div class=\"navbar\">\n" + " <a href=\"#\" class=\"active\">Home</a>\n" + " <a href=\"#\">Link</a>\n" + " <a href=\"#\">Link</a>\n" + " <a href=\"#\" class=\"right\">Link</a>\n" + "</div>\n\n" + "<div class=\"row\">\n" + " <div class=\"side\">\n" + " <h2>About Me</h2>\n" + " <h5>Photo of me:</h5>\n" + " <div class=\"fakeimg\" style=\"height:200px;\">Image</div>\n" + " <p>Some text about me in culpa qui officia deserunt mollit anim..</p>\n" + " <h3>More Text</h3>\n" + " <p>Lorem ipsum dolor sit ame.</p>\n" + " <div class=\"fakeimg\" style=\"height:60px;\">Image</div><br>\n" + " <div class=\"fakeimg\" style=\"height:60px;\">Image</div><br>\n" + " <div class=\"fakeimg\" style=\"height:60px;\">Image</div>\n" + " </div>\n" + " <div class=\"main\">\n" + " <h2>TITLE HEADING</h2>\n" + " <h5>Title description, Dec 7, 2017</h5>\n" + " <div class=\"fakeimg\" style=\"height:200px;\">Image</div>\n" + " <p>Some text..</p>\n" + " <p>Sunt in culpa qui officia deserunt mollit anim id est laborum consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco.</p>\n" + " <br>\n" + " <h2>TITLE HEADING</h2>\n" + " <h5>Title description, Sep 2, 2017</h5>\n" + " <div class=\"fakeimg\" style=\"height:200px;\">Image</div>\n" + " <p>Some text..</p>\n" + " <p>Sunt in culpa qui officia deserunt mollit anim id est laborum consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco.</p>\n" + " </div>\n" + "</div>\n\n" + "<div class=\"footer\">\n" + " <h2>Footer</h2>\n" + "</div>\n\n" + "</body>"; 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