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 = "^(((ht|f)(tp)(s)?(:\\/\\/))?(([0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3})|(([a-zA-Z\\-0-9]+\\.)+[a-zA-Z]{2,}))(:\\d{1,5})?((\\/)([\\w\\.~%-]+))*(\\/)?((\\?)(([\\w]+)(=[\\w\\.~%-]+)?((&)([\\w]+)(=[\\w\\.~%-]+)?)*)?)?((#)((([\\w]+(=[\\w\\,\\*\\.~%-]+)?)(&[\\w]+(=[\\w\\,\\*\\.~%-]+)?)*)|(:~:text=([\\w\\.~%-]+\\,)?([\\w\\.~%-]+)(\\,[\\w\\.~%-]+){0,2}))?)?)$"; final String string = "//Base case\n" + "17hieng.com\n" + "17hieng.com.my\n" + "www.17hieng.com.my\n" + "www.edu.17hieng.com.my\n" + "192.168.1.1\n\n" + "//With protocol\n" + "http://17hieng.com\n" + "https://192.168.1.1\n\n" + "//With Port\n" + "http://17hieng.com:8080\n" + "https://192.168.1.1:443\n\n" + "//With Path\n" + "www.edu.17hieng.com.my/edu\n" + "192.168.1.1/edu/\n" + "http://17hieng.com/edu/edu\n" + "https://192.168.1.1/\n\n\n" + "//With query\n" + "www.edu.17hieng.com.my?query=a&b=c\n" + "192.168.1.1/edu/?query=a&b=c@a.com\n" + "http://17hieng.com/edu/edu?query=a\n" + "https://192.168.1.1/?query=a&b&c=1\n\n\n" + "//With Fragment\n" + "www.edu.17hieng.com.my#about\n" + "192.168.1.1/edu?#line=10,20\n" + "192.168.1.1/edu/?query=a#t=40,8.0&xywh=160,120,320,240\n" + "http://17hieng.com/edu/edu?query=a#:~:text=prefix-,textStart,textEnd,-suffix\n" + "https://192.168.1.1/?query=a&b&c=1#\n\n" + "//domain only\n" + "17hieng.com\n" + "edu.17hieng.com\n" + "17hieng.com/\n" + "edu.17hieng.com/\n\n" + "//domain + https protocol\n" + "https://17hieng.com\n" + "https://edu.17hieng.com\n" + "https://17hieng.com/\n" + "https://edu.17hieng.com/\n\n" + "//domain + http protocol\n" + "http://17hieng.com\n" + "http://edu.17hieng.com\n" + "http://17hieng.com/\n" + "http://edu.17hieng.com/\n\n\n" + "//domain + file path\n" + "17hieng.com/cpp\n" + "edu.17hieng.com/cpp\n" + "17hieng.com/cpp/\n" + "edu.17hieng.com/cpp/\n\n" + "//domain + https protocol + file path\n" + "https://17hieng.com/cpp\n" + "https://edu.17hieng.com/cpp\n" + "https://17hieng.com/cpp/\n" + "https://edu.17hieng.com/cpp/\n\n" + "//domain + http protocol + file path\n" + "http://17hieng.com/cpp\n" + "http://edu.17hieng.com/cpp\n" + "http://17hieng.com/cpp/\n" + "http://edu.17hieng.com/cpp/\n\n" + "//domain + multiple folder file path\n" + "17hieng.com/cpp/intro\n" + "edu.17hieng.com/cpp/intro\n" + "17hieng.com/cpp/intro/\n" + "edu.17hieng.com/cpp/intro/\n\n" + "//domain + https protocol + multiple folder file path\n" + "https://17hieng.com/cpp/intro\n" + "https://edu.17hieng.com/cpp/intro\n" + "https://17hieng.com/cpp/intro/\n" + "https://edu.17hieng.com/cpp/intro/\n\n" + "//domain + http protocol + multiple folder file path\n" + "http://17hieng.com/cpp/intro\n" + "http://edu.17hieng.com/cpp/intro\n" + "http://17hieng.com/cpp/intro/\n" + "http://edu.17hieng.com/cpp/intro/\n\n" + "//domain + ?\n" + "17hieng.com?\n" + "edu.17hieng.com?\n" + "17hieng.com/?\n" + "edu.17hieng.com/?\n\n" + "//domain + https protocol + ?\n" + "https://17hieng.com?\n" + "https://edu.17hieng.com?\n" + "https://17hieng.com/?\n" + "https://edu.17hieng.com/?\n\n" + "//domain + http protocol + ?\n" + "http://17hieng.com?\n" + "http://edu.17hieng.com?\n" + "http://17hieng.com/?\n" + "http://edu.17hieng.com/?\n\n\n" + "//domain + file path + ?\n" + "17hieng.com/cpp?\n" + "edu.17hieng.com/cpp?\n" + "17hieng.com/cpp/?\n" + "edu.17hieng.com/cpp/?\n\n" + "//domain + https protocol + file path + ?\n" + "https://17hieng.com/cpp?\n" + "https://edu.17hieng.com/cpp?\n" + "https://17hieng.com/cpp/?\n" + "https://edu.17hieng.com/cpp/?\n\n" + "//domain + http protocol + file path + ?\n" + "http://17hieng.com/cpp?\n" + "http://edu.17hieng.com/cpp?\n" + "http://17hieng.com/cpp/?\n" + "http://edu.17hieng.com/cpp/?\n\n" + "//domain + multiple folder file path + ?\n" + "17hieng.com/cpp/intro?\n" + "edu.17hieng.com/cpp/intro?\n" + "17hieng.com/cpp/intro/?\n" + "edu.17hieng.com/cpp/intro/?\n\n" + "//domain + https protocol + multiple folder file path + ?\n" + "https://17hieng.com/cpp/intro?\n" + "https://edu.17hieng.com/cpp/intro?\n" + "https://17hieng.com/cpp/intro/?\n" + "https://edu.17hieng.com/cpp/intro/?\n\n" + "//domain + http protocol + multiple folder file path + ?\n" + "http://17hieng.com/cpp/intro?\n" + "http://edu.17hieng.com/cpp/intro?\n" + "http://17hieng.com/cpp/intro/?\n" + "http://edu.17hieng.com/cpp/intro/?\n\n" + "//domain + parameter\n" + "17hieng.com?name\n" + "edu.17hieng.com?name\n" + "17hieng.com/?name\n" + "edu.17hieng.com/?name\n\n" + "//domain + https protocol + parameter\n" + "https://17hieng.com?name\n" + "https://edu.17hieng.com?name\n" + "https://17hieng.com/?name\n" + "https://edu.17hieng.com/?name\n\n" + "//domain + http protocol + parameter\n" + "http://17hieng.com?name\n" + "http://edu.17hieng.com?name\n" + "http://17hieng.com/?name\n" + "http://edu.17hieng.com/?name\n\n\n" + "//domain + file path + parameter\n" + "17hieng.com/cpp?name\n" + "edu.17hieng.com/cpp?name\n" + "17hieng.com/cpp/?name\n" + "edu.17hieng.com/cpp/?name\n\n" + "//domain + https protocol + file path + parameter\n" + "https://17hieng.com/cpp?name\n" + "https://edu.17hieng.com/cpp?name\n" + "https://17hieng.com/cpp/?name\n" + "https://edu.17hieng.com/cpp/?name\n\n" + "//domain + http protocol + file path + parameter\n" + "http://17hieng.com/cpp?name\n" + "http://edu.17hieng.com/cpp?name\n" + "http://17hieng.com/cpp/?name\n" + "http://edu.17hieng.com/cpp/?name\n\n" + "//domain + multiple folder file path + parameter\n" + "17hieng.com/cpp/intro?name\n" + "edu.17hieng.com/cpp/intro?name\n" + "17hieng.com/cpp/intro/?name\n" + "edu.17hieng.com/cpp/intro/?name\n\n" + "//domain + https protocol + multiple folder file path + parameter\n" + "https://17hieng.com/cpp/intro?name\n" + "https://edu.17hieng.com/cpp/intro?name\n" + "https://17hieng.com/cpp/intro/?name\n" + "https://edu.17hieng.com/cpp/intro/?name\n\n" + "//domain + http protocol + multiple folder file path + parameter\n" + "http://17hieng.com/cpp/intro?name\n" + "http://edu.17hieng.com/cpp/intro?name\n" + "http://17hieng.com/cpp/intro/?name\n" + "http://edu.17hieng.com/cpp/intro/?name\n\n" + "//domain + parameter\n" + "17hieng.com?name=CheeHieng\n" + "edu.17hieng.com?name=Chee%20Hieng\n" + "17hieng.com/?name=Chee%20Hieng\n" + "edu.17hieng.com/?name=Chee%20Hieng\n\n" + "//domain + https protocol + parameter\n" + "https://17hieng.com?name=Chee%20Hieng\n" + "https://edu.17hieng.com?name=Chee%20Hieng\n" + "https://17hieng.com/?name=Chee%20Hieng\n" + "https://edu.17hieng.com/?name=Chee%20Hieng\n\n" + "//domain + http protocol + parameter\n" + "http://17hieng.com?name=Chee%20Hieng\n" + "http://edu.17hieng.com?name=Chee%20Hieng\n" + "http://17hieng.com/?name=Chee%20Hieng\n" + "http://edu.17hieng.com/?name=Chee%20Hieng\n\n\n" + "//domain + file path + parameter\n" + "17hieng.com/cpp?name=Chee%20Hieng\n" + "edu.17hieng.com/cpp?name=Chee%20Hieng\n" + "17hieng.com/cpp/?name=Chee%20Hieng\n" + "edu.17hieng.com/cpp/?name=Chee%20Hieng\n\n" + "//domain + https protocol + file path + parameter\n" + "https://17hieng.com/cpp?name=Chee%20Hieng\n" + "https://edu.17hieng.com/cpp?name=Chee%20Hieng\n" + "https://17hieng.com/cpp/?name=Chee%20Hieng\n" + "https://edu.17hieng.com/cpp/?name=Chee%20Hieng\n\n" + "//domain + http protocol + file path + parameter\n" + "http://17hieng.com/cpp?name=Chee%20Hieng\n" + "http://edu.17hieng.com/cpp?name=Chee%20Hieng\n" + "http://17hieng.com/cpp/?name=Chee%20Hieng\n" + "http://edu.17hieng.com/cpp/?name=Chee%20Hieng\n\n" + "//domain + multiple folder file path + parameter\n" + "17hieng.com/cpp/intro?name=Chee%20Hieng\n" + "edu.17hieng.com/cpp/intro?name=Chee%20Hieng\n" + "17hieng.com/cpp/intro/?name=Chee%20Hieng\n" + "edu.17hieng.com/cpp/intro/?name=Chee%20Hieng\n\n" + "//domain + https protocol + multiple folder file path + parameter\n" + "https://17hieng.com/cpp/intro?name=Chee%20Hieng\n" + "https://edu.17hieng.com/cpp/intro?name=Chee%20Hieng\n" + "https://17hieng.com/cpp/intro/?name=Chee%20Hieng\n" + "https://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng\n\n" + "//domain + http protocol + multiple folder file path + parameter\n" + "http://17hieng.com/cpp/intro?name=Chee%20Hieng\n" + "http://edu.17hieng.com/cpp/intro?name=Chee%20Hieng\n" + "http://17hieng.com/cpp/intro/?name=Chee%20Hieng\n" + "http://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng\n\n\n" + "//domain + mixed-parameter\n" + "17hieng.com?name=Chee%20Hieng&age&id=2200282\n" + "edu.17hieng.com?name=Chee%20Hieng&age&id=2200282\n" + "17hieng.com/?name=Chee%20Hieng&age&id=2200282\n" + "edu.17hieng.com/?name=Chee%20Hieng&age&id=2200282\n\n" + "//domain + https protocol + multi-parameter\n" + "https://17hieng.com?name=Chee%20Hieng&age&id=2200282\n" + "https://edu.17hieng.com?name=Chee%20Hieng&age&id=2200282\n" + "https://17hieng.com/?name=Chee%20Hieng&age&id=2200282\n" + "https://edu.17hieng.com/?name=Chee%20Hieng&age&id=2200282\n\n" + "//domain + http protocol + multi-parameter\n" + "http://17hieng.com?name=Chee%20Hieng&age&id=2200282\n" + "http://edu.17hieng.com?name=Chee%20Hieng&age&id=2200282\n" + "http://17hieng.com/?name=Chee%20Hieng&age&id=2200282\n" + "http://edu.17hieng.com/?name=Chee%20Hieng&age&id=2200282\n\n\n" + "//domain + file path + multi-parameter\n" + "17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282\n" + "edu.17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282\n" + "17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282\n" + "edu.17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282\n\n" + "//domain + https protocol + file path + multi-parameter\n" + "https://17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282\n" + "https://edu.17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282\n" + "https://17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282\n" + "https://edu.17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282\n\n" + "//domain + http protocol + file path + multi-parameter\n" + "http://17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282\n" + "http://edu.17hieng.com/cpp?name=Chee%20Hieng&age&id=2200282\n" + "http://17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282\n" + "http://edu.17hieng.com/cpp/?name=Chee%20Hieng&age&id=2200282\n\n" + "//domain + multiple folder file path + multi-parameter\n" + "17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282\n" + "edu.17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282\n" + "17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282\n" + "edu.17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282\n\n" + "//domain + https protocol + multiple folder file path + multi-parameter\n" + "https://17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282\n" + "https://edu.17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282\n" + "https://17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282\n" + "https://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282\n\n" + "//domain + http protocol + multiple folder file path + parameter\n" + "http://17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282\n" + "http://edu.17hieng.com/cpp/intro?name=Chee%20Hieng&age&id=2200282\n" + "http://17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200282\n" + "http://edu.17hieng.com/cpp/intro/?name=Chee%20Hieng&age&id=2200%20282_\n\n\n\n\n" + "//Invalid\n" + "htp://17hieng.com\n" + "17Hieng.c\n" + "http:/17hieng.com\n" + "https//17h.my\n" + "code.17Hi@ng.com\n" + "17hieng.com/?=1\n" + "17hineg.com//\n" + "17Hieng.com/hello world\n" + "17Hieng.com<\n" + "17hieng.com/h=1\n" + "17Hieng.com=2\n" + "17hieng.com/?hi=&version\n" + "17hieng.com/?hi=1&version&&\n" + "17hieng.com/?hi=1&version&q%20\n"; 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