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

const regex = /([^\n\r:]*)(:[ \t])[ \t]*([^\n\r]*)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('([^\\n\\r:]*)(:[ \\t])[ \\t]*([^\\n\\r]*)', 'gm') const str = `NetRange: 2001:4860:: - 2001:4860:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF CIDR: 2001:4860::/32 NetName: GOOGLE-IPV6 NetHandle: NET6-2001-4860-1 Parent: ARIN-004 (NET6-2001-4800-0) NetType: Direct Allocation OriginAS: AS15169 Organization: Google LLC (GOGL) RegDate: 2005-03-14 Updated: 2012-02-24 Ref: https://rdap.arin.net/registry/ip/2001:4860:: OrgName: Google LLC OrgId: GOGL Address: 1600 Amphitheatre Parkway City: Mountain View StateProv: CA PostalCode: 94043 Country: US RegDate: 2000-03-30 Updated: 2019-10-31 Comment: Please note that the recommended way to file abuse complaints are located in the following links. Comment: Comment: To report abuse and illegal activity: https://www.google.com/contact/ Comment: Comment: For legal requests: http://support.google.com/legal Comment: Comment: Regards, Comment: The Google Team Ref: https://rdap.arin.net/registry/entity/GOGL OrgTechHandle: ZG39-ARIN OrgTechName: Google LLC OrgTechPhone: +1-650-253-0000 OrgTechEmail: arin-contact@google.com OrgTechRef: https://rdap.arin.net/registry/entity/ZG39-ARIN OrgAbuseHandle: ABUSE5250-ARIN OrgAbuseName: Abuse OrgAbusePhone: +1-650-253-0000 OrgAbuseEmail: network-abuse@google.com OrgAbuseRef: https://rdap.arin.net/registry/entity/ABUSE5250-ARIN RNOCHandle: ZG39-ARIN RNOCName: Google LLC RNOCPhone: +1-650-253-0000 RNOCEmail: arin-contact@google.com RNOCRef: https://rdap.arin.net/registry/entity/ZG39-ARIN RTechHandle: ZG39-ARIN RTechName: Google LLC RTechPhone: +1-650-253-0000 RTechEmail: arin-contact@google.com RTechRef: https://rdap.arin.net/registry/entity/ZG39-ARIN RAbuseHandle: ZG39-ARIN RAbuseName: Google LLC RAbusePhone: +1-650-253-0000 RAbuseEmail: arin-contact@google.com RAbuseRef: https://rdap.arin.net/registry/entity/ZG39-ARIN`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions