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 = /mailto:([^\"]+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('mailto:([^\\"]+)', 'gm') const str = `<p><a href="mailto:info@tartaytantas.es"> info@tartaytantas.es</a></p> <p>No cogemos pedidos por mail.</p> <p></p> </div><!-- .entry-content --> <footer class="entry-footer"> </footer><!-- .entry-footer --> </div> </article><!-- #post-## --> </main><!-- #main --> </div><!-- #primary --> </div></div> <footer id="colophon" class="site-footer" role="contentinfo" itemscope="" itemtype="http://schema.org/WPFooter"> <div class="container"> <div class="footer-t"> <div class="row"> <div class="three-cols"> <div class="col"> </div> <div class="col center"> <section class="widget widget_contact_form"> </section> </div> <div class="col"> </div> </div> </div> </div> <p><a href="mailto:info@tartaytantas.es"> info@tartaytantas.es</a></p> <div class="site-info"> <span> ©2020 <a href="http://tartaytantas.es/">Tartaytantas - Tartas y bizccochos a domicilio en Aravaca</a>. </span> Bakes and Cakes | Desarrollado por <a href="https://rarathemes.com/" rel="nofollow" target="_blank"> Rara Theme </a> Funciona gracias a <a href="https://wordpress.org/">WordPress.</a> </div><!-- .site-info --> </div> </footer><!-- #colophon --> <div class="overlay"></div> <a href="javascript:void(0);" class="btn-top"><span>Arriba</span></a> </div><!-- #acc-content --> </div><!-- #page --> <script type="text/javascript" src="https://secureservercdn.net/160.153.137.170/zm5.b57.myftpupload.com/wp-content/themes/bakes-and-cakes/js/owl.carousel.min.js javascriptvue.jsEdit tags `; // 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