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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /^(?<domain>[^/?#]+) wants you to sign in with your Ethereum account:\n(?<address>0x[a-zA-Z0-9]{40})\n\n((?<statement>[^\n]+)\n)?\nURI: (?<uri>(([^:?#]+):)?(([^?#]*))?([^?#]*)(\?([^#]*))?(#(.*))??)\nVersion: (?<version>1)\nChain ID: (?<chain_id>[0-9]+)\nNonce: (?<nonce>[a-zA-Z0-9]{8,})\nIssued At: (?<issued_at>([0-9]+)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])[Tt]([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]|60)(\.[0-9]+)?(([Zz])|([+|\-]([01][0-9]|2[0-3]):[0-5][0-9])))(\nExpiration Time: (?<expiration_time>([0-9]+)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])[Tt]([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]|60)(\.[0-9]+)?(([Zz])|([+|\-]([01][0-9]|2[0-3]):[0-5][0-9]))))?(\nNot Before: (?<not_before>([0-9]+)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])[Tt]([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]|60)(\.[0-9]+)?(([Zz])|([+|\-]([01][0-9]|2[0-3]):[0-5][0-9]))))?(\nRequest ID: (?<request_id>[-._~!$&'()*+,;=:@%a-zA-Z0-9]*))?(\nResources:(?<resources>(\n- (([^:?#]+):)?(([^?#]*))?([^?#]*)(\?([^#]*))?(#(.*))??)+))?$/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('^(?<domain>[^\/?#]+) wants you to sign in with your Ethereum account:\\n(?<address>0x[a-zA-Z0-9]{40})\\n\\n((?<statement>[^\\n]+)\\n)?\\nURI: (?<uri>(([^:?#]+):)?(([^?#]*))?([^?#]*)(\\?([^#]*))?(#(.*))??)\\nVersion: (?<version>1)\\nChain ID: (?<chain_id>[0-9]+)\\nNonce: (?<nonce>[a-zA-Z0-9]{8,})\\nIssued At: (?<issued_at>([0-9]+)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])[Tt]([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]|60)(\\.[0-9]+)?(([Zz])|([+|\\-]([01][0-9]|2[0-3]):[0-5][0-9])))(\\nExpiration Time: (?<expiration_time>([0-9]+)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])[Tt]([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]|60)(\\.[0-9]+)?(([Zz])|([+|\\-]([01][0-9]|2[0-3]):[0-5][0-9]))))?(\\nNot Before: (?<not_before>([0-9]+)-(0[1-9]|1[012])-(0[1-9]|[12][0-9]|3[01])[Tt]([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]|60)(\\.[0-9]+)?(([Zz])|([+|\\-]([01][0-9]|2[0-3]):[0-5][0-9]))))?(\\nRequest ID: (?<request_id>[-._~!$&\'()*+,;=:@%a-zA-Z0-9]*))?(\\nResources:(?<resources>(\\n- (([^:?#]+):)?(([^?#]*))?([^?#]*)(\\?([^#]*))?(#(.*))??)+))?$', 'g') const str = `service.org wants you to sign in with your Ethereum account: 0xe5A12547fe4E872D192E3eCecb76F2Ce1aeA4946 I accept the ServiceOrg Terms of Service: https://service.org/tos URI: https://service.org/login Version: 1 Chain ID: 1 Nonce: 12341234 Issued At: 2022-03-17T12:45:13.610Z Expiration Time: 2023-03-17T12:45:13.610Z Not Before: 2022-03-17T12:45:13.610Z Request ID: some_id Resources: - https://service.org/login`; // 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