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

Generated Code

const regex = /(<\/strong>\n\s{4}|<\/strong>&nbsp;\n\s{4})?<br>/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('(<\\\/strong>\\n\\s{4}|<\\\/strong>&nbsp;\\n\\s{4})?<br>', 'g') const str = `<p><strong>It was a weak bit.</strong>&nbsp; <br>Because it&rsquo;s already been done. If he had been like, &ldquo;I don&rsquo;t know, do you want to go to the La Brea tar pits and scoop some tar out and give ourselves a facial and burn ourselves and then only be able to know each other?&rdquo; I would be like, &ldquo;Haa, what?! Okay.&rdquo; I mean, something new is going on here. He basically did the equivalent of like when guys do &ldquo;fat guy in a little coat,&rdquo; and they act like it&rsquo;s not a Chris Farley callback. It&rsquo;s like, this is a joke that&rsquo;s in our system, so you&rsquo;re a little bit unoriginal or even worse, you don&rsquo;t know you&rsquo;re unoriginal.&nbsp;</p> <p><strong>Does he know it&rsquo;s you?</strong>&nbsp; <br>I do think he knew that I was a comedian named Jenny. So anyway, he&rsquo;s like, &ldquo;Let&rsquo;s go to the Renaissance fair,&rdquo; and I call my friends, and I&rsquo;m like, &ldquo;I&rsquo;m not going on this date.&rdquo; And they&rsquo;re like, &ldquo;Oh Jenny, come on, don&rsquo;t be so closed down, you need to get out there.&rdquo; I&rsquo;m like, &ldquo;UGH, fine.&rdquo; Then we have a series of text messages back and forth that I&rsquo;m just kind of like, <em>What is this? Is this what dating is like?</em> I was with my ex-husband for nine years, then I was in a very serious relationship that was passionate for a year, and I&rsquo;m like, I don&rsquo;t know, maybe I just don&rsquo;t know what&rsquo;s going on. And he&rsquo;s asking me these questions that I&rsquo;m like, What. The. Fuck. Why don&rsquo;t you just wait?</p> <p><strong>What is he asking you?</strong>&nbsp; <br>Like, &ldquo;Where was the last place you flew on an airplane?&rdquo; And I&rsquo;m not a rude or cruel woman, but I was like, I don&rsquo;t... dude... just wait. Sit me down, I&rsquo;ll tell you anything, just wait. Just wait until Saturday.</p> <p><strong>Also, that&rsquo;s the kind of question that is like, &ldquo;I&rsquo;m gonna go on the internet and search random questions to ask someone.&rdquo;</strong>&nbsp; <br>Yeah, it&rsquo;s not great. It&rsquo;s a real speed-dating question. I would love it in other circumstances if it was like a page in <em>Entertainment Weekly</em>, you know? So then I&rsquo;m like, &ldquo;I made us a reservation at this restaurant, will you meet me there?&rdquo; He&rsquo;s like, &ldquo;Yes, is it fancy?&rdquo; I&rsquo;m like, &ldquo;No,&rdquo; and he&rsquo;s like, &ldquo;Okay, should I wear something like this?&rdquo; And he sends me a picture of a knight&rsquo;s costume. Like from the Renaissance fair. At which point I&rsquo;m like what the fuck, dude? Because I didn&rsquo;t even jump on this riff in the first place. It&rsquo;s not like I was like, &ldquo;Yes, and I will wear my wench&#39;s costume and bring a cup of mead!&rdquo; I&rsquo;m just like... Heh?! What? Why are you doing this?</p> <p><strong>You didn&rsquo;t respond positively to the bit.</strong> <br>Never. Anyway, on the day of the date, I was like, &ldquo;How will I know it&rsquo;s you?&rdquo; And I thought he would be like, &ldquo;I&rsquo;m 6&rsquo;1&rdquo; and I&rsquo;ve got a beard,&rdquo; or some <p><br></p> <p><br></p> <p><br></p>`; // 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