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

Substitution

Processing...

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 = "(?i)<label id=\"\\{[\\d\\w-]+\\}\">([a-z ]+)<\\/label>"; final String string = "<p>\n" + "<title>Contact Us</title>\n" + "</p>\n" + "<table dropzone=\"copy\">\n" + " <tbody>\n" + " <tr>\n" + " <td class=\"label\" style=\"cursor: default;\">Full Name</td>\n" + " <td style=\n" + "\"cursor: default;\">[<label id=\"{0a4a7240-9606-416a-bf7b-ef11a47cca8e}\">First name</label>] [<label id=\"{94263497-683b-46f9-ba0f-69f4c2736598}\">Last name</label>]</td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"label\" style=\"cursor: d\n" + "efault;\">Telephone</td>\n" + " <td style=\"cursor: default;\">[<label id=\"{ce68e02e-e9fd-40ee-9375-ee1b05972e9b}\">Phone</label>]</td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"label\" style=\"cursor: default;\">Email</td>\n" + " <td style=\"cursor: default;\">[<label id=\"{411b580e-f7e9-4dd2-a70d-947385360cd0}\">Email</label>]</td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"label\" style=\"cursor: default;\">Message</td>\n" + " <td style=\"cursor: default;\">[\n" + "<label id=\"{13e2ff23-135c-4c6d-beb4-2960a533cb98}\">Your Message</label>]</td>\n" + " </tr>\n" + " <tr>\n" + " <td class=\"label\" style=\"cursor: default;\">Company</td>\n" + " <td style=\"cursor: default;\">[<label id=\"{c3f22c3a-8fc1\n" + "-48a4-8d6a-fe346024ca2b}\">Company</label>]</td>\n" + " </tr>\n" + " </tbody>\n" + "</table>\n" + "<p> </p>\n" + "<p> </p>"; final String subst = "$1"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + 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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html