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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "Reg: Email:"; final String string = "Hi,\n" + "Congrats, your offer on a Ford Ka for the price of £2,000.00, was the winning offer!\n" + " \n" + "Car Details\n" + " Ford Ka \n" + "Model: Ford Ka\n" + "Reg: LN61XVW\n" + "Fee: £229.0\n" + "Distance: 32 miles\n" + "Mileage: 28709\n" + "Car age: 13\n" + "Colour: BLACK\n" + "See customer details\n\n" + "You’ll need to find a time that’s right for both parties so you can inspect the vehicle and make sure it looks as good as advertised.\n\n" + "Ask us to collect for you or pick it up yourself and arrange payment with the seller.\n" + " \n" + "Customer Contact Details\n" + " \n" + "Name: Donna Irwin\n" + "Phone: +447884015643\n" + "Email: donna.irwin@btinternet.com\n" + "Postcode: AL1 2ET\n" + " \n" + "Follow the link below to get in touch and exchange details.\n" + "Contact the seller here\n" + "Use the help link below if you have any questions.\n" + " \n" + " \n" + "Happy Hunting,\n" + "The Carwow Team"; 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