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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

Code Generator

Language

Generated Code

const regex = /[^\n.!?:]*(?:thanks[ .?!]*$|thank[ -]you[ .?!]*$|help[ .?!]*$|(?:please|help|suggest(?:ions)|thanks)\b[^\n.!?:]*\b(?:help|ap+reciat\w*|me|advan\w*|a ?lot)\b[^\n.!?:]*)[.!?_*]*[ ]*/gim; // Alternative syntax using RegExp constructor // const regex = new RegExp('[^\\n.!?:]*(?:thanks[ .?!]*$|thank[ -]you[ .?!]*$|help[ .?!]*$|(?:please|help|suggest(?:ions)|thanks)\\b[^\\n.!?:]*\\b(?:help|ap+reciat\\w*|me|advan\\w*|a ?lot)\\b[^\\n.!?:]*)[.!?_*]*[ ]*', 'gim') const str = `I don't know what's going on. Any help would be appreciated. How can I do this? Any suggestions are appreciated :) Please help me, i will thank you. How I do this? I hope you guys can help me. Thanks for any help. All suggestions are appreciated, thanks Thanks in advance. Could you help me? I hope you can please help me buddy! please help Can someone please guide me where I am going wrong ? I have no teacher or any instructor because I am learning programming on my own, so please any help is appreciated. Thanks thanks in advance! thanks in advantage! Thanks in advance! kindly help me with the step by step solution.. thanks in advance __Thanks in advance.__ Thanks a lot! Thank you!!! also id like to thank you for any help in advance. let me first state that i am aware of possible security issues and will address those accordingly. thanks!! Do Not Match: Software for tanks. It would please my boss. Please look at this example. Thanks to Microsoft, I can no longer log in to my email. Please stop sending me emails Microsoft! << Nobody has ever said that on SO. Please don't ever do this. << This is a common statement in PHP/MySQL answers! Please don't tell me you are using regular expressions to validate urls when there's the Uri.TryCreate method. Thank you to AndrewMalinnkov for the answer!`; // 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