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 = "([^\\n\\r:]*)(:[ \\t])[ \\t]*([^\\n\\r]*)"; final String string = "NetRange: 2001:4860:: - 2001:4860:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF\n" + "CIDR: 2001:4860::/32\n" + "NetName: GOOGLE-IPV6\n" + "NetHandle: NET6-2001-4860-1\n" + "Parent: ARIN-004 (NET6-2001-4800-0)\n" + "NetType: Direct Allocation\n" + "OriginAS: AS15169\n" + "Organization: Google LLC (GOGL)\n" + "RegDate: 2005-03-14\n" + "Updated: 2012-02-24\n" + "Ref: https://rdap.arin.net/registry/ip/2001:4860::\n\n" + "OrgName: Google LLC\n" + "OrgId: GOGL\n" + "Address: 1600 Amphitheatre Parkway\n" + "City: Mountain View\n" + "StateProv: CA\n" + "PostalCode: 94043\n" + "Country: US\n" + "RegDate: 2000-03-30\n" + "Updated: 2019-10-31\n" + "Comment: Please note that the recommended way to file abuse complaints are located in the following links. \n" + "Comment: \n" + "Comment: To report abuse and illegal activity: https://www.google.com/contact/\n" + "Comment: \n" + "Comment: For legal requests: http://support.google.com/legal \n" + "Comment: \n" + "Comment: Regards, \n" + "Comment: The Google Team\n" + "Ref: https://rdap.arin.net/registry/entity/GOGL\n\n" + "OrgTechHandle: ZG39-ARIN\n" + "OrgTechName: Google LLC\n" + "OrgTechPhone: +1-650-253-0000 \n" + "OrgTechEmail: arin-contact@google.com\n" + "OrgTechRef: https://rdap.arin.net/registry/entity/ZG39-ARIN\n" + "OrgAbuseHandle: ABUSE5250-ARIN\n" + "OrgAbuseName: Abuse\n" + "OrgAbusePhone: +1-650-253-0000 \n" + "OrgAbuseEmail: network-abuse@google.com\n" + "OrgAbuseRef: https://rdap.arin.net/registry/entity/ABUSE5250-ARIN\n" + "RNOCHandle: ZG39-ARIN\n" + "RNOCName: Google LLC\n" + "RNOCPhone: +1-650-253-0000 \n" + "RNOCEmail: arin-contact@google.com\n" + "RNOCRef: https://rdap.arin.net/registry/entity/ZG39-ARIN\n" + "RTechHandle: ZG39-ARIN\n" + "RTechName: Google LLC\n" + "RTechPhone: +1-650-253-0000 \n" + "RTechEmail: arin-contact@google.com\n" + "RTechRef: https://rdap.arin.net/registry/entity/ZG39-ARIN\n" + "RAbuseHandle: ZG39-ARIN\n" + "RAbuseName: Google LLC\n" + "RAbusePhone: +1-650-253-0000 \n" + "RAbuseEmail: arin-contact@google.com\n" + "RAbuseRef: https://rdap.arin.net/registry/entity/ZG39-ARIN"; 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