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 = "name\\s?[a-z]{0,2}\\s([A-Z]{1}[a-z]+)"; final String string = "This is a spotted Lipitor Rumpelstiltskin named Alphred. He can't wait for the Turkey. 10/10 would pet really well https://t.co/6GUGO7azNX\n\n" + "Sorry for the lack of posts today. I came home from school and had to spend quality time with my puppo. Her name is Zoey and she's 13/10 https://t.co/BArWupFAn0\n\n" + "Ladies and gentlemen... I found Pipsy. He may have changed his name to Pablo, but he never changed his love for the sea. Pupgraded to 14/10 https://t.co/lVU5GyNFen\n\n" + "HI. MY. NAME. IS. BOOMER. AND. I. WANT. TO. SAY. IT'S. H*CKIN. RIDICULOUS. THAT. DOGS. CAN'T VOTE. ABSOLUTE. CODSWALLUP. THANK. YOU. 13/10 https://t.co/SqKJPwbQ2g\n\n" + "Name a more iconic quartet... I'll wait. 13/10 for all https://t.co/kCLgD8687T\n\n" + "RT @dog_rates: This a Norwegian Pewterschmidt named Tickles. Ears for days. 12/10 I care deeply for Tickles https://t.co/0aDF62KVP7\n\n" + "When bae calls your name from across the room. 12/10 (vid by @christinemcc98) https://t.co/xolcXA6gxe\n\n" + "We normally don't rate bears but this one seems nice. Her name is Thea. Appears rather fluffy. 10/10 good bear https://t.co/fZc7MixeeT\n\n" + "This pup's name is Sabertooth (parents must be cool). Ears for days. Jumps unannounced. 9/10 would pet diligently https://t.co/iazoiNUviP\n\n" + "I would do radical things in the name of Dog God. I'd believe every word in that book. 10/10 https://t.co/9ZuGAmLZDR"; 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