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 = "((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\/([0-9]+))|((([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]{1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:){1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|[0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:(:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]{1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9]))\\/([0-9]+))"; final String string = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n" + "<reg:registerSocResources updateTime=\"2023-08-23T17:00:00+03:00\" formatVersion=\"1.0\" xmlns:reg=\"http://rkn.gov.ru/register/socResources\" xmlns:tns=\"http://rkn.gov.ru/register/socResources\">\n" + " <content id=\"1\" hash=\"c74d571742a6c706828b803d5190e566\" includeTime=\"2022-01-26T22:00:00+03:00\">\n" + " <resourceName><![CDATA[Единый портал государственных и муниципальных услуг (Госуслуги)]]></resourceName>\n" + " <domain><![CDATA[gosuslugi.ru]]></domain>\n" + " <ipSubnet>37.220.160.0/21</ipSubnet>\n" + " <ipSubnet>46.235.184.0/21</ipSubnet>\n" + " <ipSubnet>93.93.88.0/21</ipSubnet>\n" + " <ipSubnet>78.41.104.0/21</ipSubnet>\n" + " <ipSubnet>185.17.168.0/22</ipSubnet>\n" + " <ipSubnet>212.193.144.0/20</ipSubnet>\n" + " <ipSubnet>195.208.30.60/30</ipSubnet>\n" + " <ipSubnet>195.209.64.0/21</ipSubnet>\n" + " <ipSubnet>195.209.80.0/20</ipSubnet>\n" + " <ipSubnet>195.208.64.0/20</ipSubnet>\n" + " <ipSubnet>195.209.75.0/25</ipSubnet>\n" + " <ipSubnet>185.38.204.18/32</ipSubnet>\n" + " <ipSubnet>109.207.0.0/20</ipSubnet>\n" + " <ipSubnet>213.59.192.0/18</ipSubnet>\n" + " </content>\n" + " <content id=\"2\" hash=\"45fcc3ee99b66673c1de92809d7ea403\" includeTime=\"2022-01-26T22:00:00+03:00\">\n" + " <resourceName><![CDATA[Социальная сеть \"ВКонтакте\"]]></resourceName>\n" + " <domain><![CDATA[vk.com]]></domain>\n" + " <ipSubnet>5.181.61.0/24</ipSubnet>\n" + " <ipSubnet>79.137.139.0/24</ipSubnet>\n" + " <ipSubnet>79.137.164.0/24</ipSubnet>\n" + " <ipSubnet>79.137.180.0/24</ipSubnet>\n" + " <ipSubnet>79.137.183.0/24</ipSubnet>\n" + " <ipSubnet>87.240.128.0/18</ipSubnet>\n" + " <ipSubnet>93.186.224.0/20</ipSubnet>\n" + " <ipSubnet>95.142.192.0/20</ipSubnet>\n" + " <ipSubnet>95.213.0.0/17</ipSubnet>\n" + " <ipSubnet>185.32.248.0/22</ipSubnet>\n" + " <ipSubnet>185.226.52.0/22</ipSubnet>\n" + " <ipSubnet>45.136.20.0/22</ipSubnet>\n" + " <ipSubnet>95.163.39.80/29</ipSubnet>\n" + " <ipSubnet>193.203.40.0/22</ipSubnet>\n" + " <ipSubnet>5.61.20.180/31</ipSubnet>\n" + " <ipSubnet>5.61.20.196/30</ipSubnet>\n" + " <ipSubnet>5.61.20.248/29</ipSubnet>\n" + " <ipSubnet>5.61.23.186/31</ipSubnet>\n" + " <ipSubnet>5.61.23.228/31</ipSubnet>\n" + " <ipSubnet>5.61.23.248/30</ipSubnet>\n" + " <ipSubnet>185.16.247.226/31</ipSubnet>\n" + " <ipSubnet>185.100.104.4/30</ipSubnet>\n" + " <ipSubnet>185.100.104.44/30</ipSubnet>\n" + " <ipSubnet>185.100.104.48/29</ipSubnet>\n" + " <ipSubnet>185.100.104.132/30</ipSubnet>\n" + " <ipSubnet>185.100.105.24/29</ipSubnet>\n" + " <ipSubnet>185.100.105.64/30</ipSubnet>\n" + " <ipSubnet>185.100.105.132/30</ipSubnet>\n" + " <ipSubnet>185.100.105.192/29</ipSubnet>\n" + " <ipSubnet>185.100.105.200/30</ipSubnet>\n" + " <ipSubnet>217.20.158.34/31</ipSubnet>\n" + " <ipSubnet>5.101.40.2/32</ipSubnet>\n" + " <ipSubnet>217.20.152.213/32</ipSubnet>\n" + " <ipSubnet>217.20.156.158/32</ipSubnet>\n" + " <ipSubnet>217.20.156.18/32</ipSubnet>\n" + " <ipSubnet>217.20.155.24/32</ipSubnet>\n" + " <ipSubnet>217.20.147.23/32</ipSubnet>\n" + " <ipSubnet>95.163.56.192/27</ipSubnet>\n" + " <ipSubnet>95.163.41.200/30</ipSubnet>\n" + " <ipSubnet>5.61.16.0/21</ipSubnet>\n" + " <ipSubnet>185.16.148.0/22</ipSubnet>\n" + " <ipSubnet>185.16.244.0/22</ipSubnet>\n" + " <ipSubnet>217.20.144.0/20</ipSubnet>\n" + " <ipSubnet>87.240.160.0/26</ipSubnet>\n" + " <ipSubnet>95.142.201.192/27</ipSubnet>\n" + " <ipSubnet>95.142.202.0/27</ipSubnet>\n" + " <ipSubnet>95.142.203.192/27</ipSubnet>\n" + " <ipSubnet>95.142.206.192/27</ipSubnet>\n" + " <ipSubnet>185.32.249.192/27</ipSubnet>\n" + " <ipSubnet>185.32.250.192/27</ipSubnet>\n" + " <ipSubnet>185.32.251.192/27</ipSubnet>\n" + " <ipSubnet>185.100.104.0/22</ipSubnet>\n" + " </content>\n" + " <ipv6Subnet>2001:0db8:11a3:09d7::/64</ipv6Subnet>"; 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