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

/
/

Test String

Code Generator

Language

Generated Code

const regex = /div id=^(.*)></; // Alternative syntax using RegExp constructor // const regex = new RegExp('div id=^(.*)><', '') const str = `<div style="outline: 1px solid blue;" class="_36bx _4-u2 _4-u8" data-testid="react-composer-root" id="u_0_18" data-reactid=".4"><div class="_4d6h _4p1p _4-u3 _57d8" data-reactid=".4.0"><div class="clearfix" data-reactid=".4.0.0"><div class="_ohe lfloat" data-reactid=".4.0.0.\$left"><div data-reactid=".4.0.0.\$left.0"><a class="_5qtm _5qtn" role="tab" aria-selected="true" label="Statut" icon="[object Object]" data-testid="status-attachment-selector" selected="" href="#" data-reactid=".4.0.0.\$left.0.0"><span class="_4-fs" data-reactid=".4.0.0.\$left.0.0.0"><i class="_5qto img sp_QiW5hJ5PiNH sx_49d0b1" data-reactid=".4.0.0.\$left.0.0.0.0"></i><span class="_5qtp" data-reactid=".4.0.0.\$left.0.0.0.1">Statut</span><span class="_5qtq" data-reactid=".4.0.0.\$left.0.0.0.2"></span></span></a><a class="_5qtm" role="tab" aria-selected="false" label="Photo/vidéo" icon="[object Object]" data-testid="media-attachment-selector" href="#" data-reactid=".4.0.0.\$left.0.1"><span class="_4-fs" data-reactid=".4.0.0.\$left.0.1.0"><i class="_5qto img sp_QiW5hJ5PiNH sx_33bc4c" data-reactid=".4.0.0.\$left.0.1.0.0"></i><span class="_5qtp" data-reactid=".4.0.0.\$left.0.1.0.1">Photo/vidéo</span><span class="_5qtq" data-reactid=".4.0.0.\$left.0.1.0.2"></span></span></a><a class="_5qtm" role="tab" aria-selected="false" label="Offre, évènement +" icon="[object Object]" href="#" data-reactid=".4.0.0.\$left.0.2"><span class="_4-fs" data-reactid=".4.0.0.\$left.0.2.0"><i class="_5qto img sp_BaO-9AbAyUH sx_98a590" data-reactid=".4.0.0.\$left.0.2.0.0"></i><span class="_5qtp" data-reactid=".4.0.0.\$left.0.2.0.1">Offre, évènement +</span><span class="_5qtq" data-reactid=".4.0.0.\$left.0.2.0.2"></span></span></a></div></div><div class="_ohf rfloat" data-reactid=".4.0.0.\$right"><div data-reactid=".4.0.0.\$right.0"><img class="_4d6i img" src="https://static.xx.fbcdn.net/rsrc.php/v2/yb/r/GsNJNwuI-UM.gif" data-reactid=".4.0.0.\$right.0.0" height="11" width="16"><span data-reactid=".4.0.0.\$right.0.1"><span class="hidden_elem _5gvy img _55ym _55yn _55yo _5d9-" aria-label="Chargement..." aria-busy="true" data-reactid=".4.0.0.\$right.0.1.0"></span><span class="_6vh _4w4v" data-reactid=".4.0.0.\$right.0.1.1"><span class="hidden_elem _3-8_ img _55ym _55yn _55yo _5d9-" aria-label="Chargement..." aria-busy="true" data-reactid=".4.0.0.\$right.0.1.1.0"></span><span aria-label="Vous publiez en tant que Mega drole" data-hover="tooltip" data-reactid=".4.0.0.\$right.0.1.1.1"><a aria-haspopup="true" aria-owns="js_i" style="max-width:200px;" class="_4z8- _55pi _2agf _4z8- _55pi _4jy0 _4jy3 _517h _51sy _59pe _42ft" href="#" type="button" data-reactid=".4.0.0.\$right.0.1.1.1.0"><span class="_55pe" data-reactid=".4.0.0.\$right.0.1.1.1.0.1"><img src="https://fbcdn-profile-a.akamaihd.net/hprofile-ak-xft1/v/t1.0-1/p32x32/1453483_555123727915438_1286693911_n.png?oh=e520e64208f4829f8307cfadce0812e8&amp;oe=56C302F3&amp;__gda__=1456503974_001e2d51c40bce6e62c31d80438f25a9" class="img" data-reactid=".4.0.0.\$right.0.1.1.1.0.1.0" height="16" width="16"><span data-reactid=".4.0.0.\$right.0.1.1.1.0.1.1"></span></span><i alt="" class="_3-99 img sp_5_FvgObiY-v sx_593e27" data-reactid=".4.0.0.\$right.0.1.1.1.0.2"></i></a></span></span></span></div></div></div></div><div class="_4zoz _4-u3" data-reactid=".4.1"><div id="js_k" data-reactid=".4.1.0"><div class="_1y-n" data-reactid=".4.1.0.0"><div class="_1y-o" data-reactid=".4.1.0.0.0"><span class="_1y-p" data-reactid=".4.1.0.0.0.0">Faites glisser un lien, des photos ou des vidéos ici</span><span class="_1y-q" data-reactid=".4.1.0.0.0.1">Déposer le lien</span><span class="_1y-r" data-reactid=".4.1.0.0.0.2">Déposer une photo/vidéo</span><span class="_1y-s" data-reactid=".4.1.0.0.0.3">Déposez les photos</span></div></div><div class="clearfix" data-reactid=".4.1.0.1"><div class="_42k7 _4bl7" data-reactid=".4.1.0.1.\$0"><div class="_3hvt" data-reactid=".4.1.0.1.\$0.0"><img class="_bth img" src="https://fbcdn-profile-a.akamaihd.net/hprofile-ak-xft1/v/t1.0-1/p40x40/1453483_555123727915438_1286693911_n.png?oh=531ded5fcd4f71ed763f8c6d683325a5&amp;oe=568FDCAF&amp;__gda__=1456525306_54b153b26c9b3c2c6a3ac05ebc0242d6" data-reactid=".4.1.0.1.\$0.0.0" height="40" width="40"></div></div><div class="_4bl9" data-reactid=".4.1.0.1.\$1"><div class="_1mwp _1mwq _5bu_ _5yk1" data-reactid=".4.1.0.1.\$1.0"><div class="_5yk2" tabindex="-2" data-reactid=".4.1.0.1.\$1.0.0"><div class="_5yw9" data-reactid=".4.1.0.1.\$1.0.0.0"><div class="_5ywb _5ywc" data-reactid=".4.1.0.1.\$1.0.0.0.0"><div class="_3br6" data-reactid=".4.1.0.1.\$1.0.0.0.0.0">Écrivez quelque chose...</div></div><div class="_5ywa" data-reactid=".4.1.0.1.\$1.0.0.0.\$editor0"><div aria-autocomplete="list" aria-expanded="false" aria-haspopup="false" aria-owns="js_j" class="_54-z" role="combobox" spellcheck="true" title="Écrivez quelque chose..." data-reactid=".4.1.0.1.\$1.0.0.0.\$editor0.0" contenteditable="true"><div data-contents="true" data-reactid=".4.1.0.1.\$1.0.0.0.\$editor0.0.0"><div data-block="true" data-offset-key="cioa-0-0" class="_209g _2vxa" data-reactid=".4.1.0.1.\$1.0.0.0.\$editor0.0.0.\$cioa"><span data-offset-key="cioa-0-0" data-reactid=".4.1.0.1.\$1.0.0.0.\$editor0.0.0.\$cioa.0:\$cioa-0-0"><br data-reactid=".4.1.0.1.\$1.0.0.0.\$editor0.0.0.\$cioa.0:\$cioa-0-0.0"></span></div></div></div></div></div></div></div></div></div><noscript data-reactid=".4.1.0.2"></noscript><div class="_3qg0" data-reactid=".4.1.0.4"></div><div data-reactid=".4.1.0.7"><div class="_5f24" data-reactid=".4.1.0.7.0"><noscript data-reactid=".4.1.0.7.0.1"></noscript><noscript data-reactid=".4.1.0.7.0.2"></noscript><noscript data-reactid=".4.1.0.7.0.3"></noscript></div><div class="_2dck _4-u3 _57d8" data-reactid=".4.1.0.7.1"><div class="clearfix" data-reactid=".4.1.0.7.1.0"><div class="_ohe lfloat" data-reactid=".4.1.0.7.1.0.\$left"><div class="_47gt" data-reactid=".4.1.0.7.1.0.\$left.0"><div class="_3xem _3xen" data-reactid=".4.1.0.7.1.0.\$left.0.0"><div class="_m _6a" data-reactid=".4.1.0.7.1.0.\$left.0.0.0"><a rel="ignore" data-hover="tooltip" aria-label="Ajoutez des photos à votre publication" class="_3xen _50hp" data-reactid=".4.1.0.7.1.0.\$left.0.0.0.0"><span class="accessible_elem" data-reactid=".4.1.0.7.1.0.\$left.0.0.0.0.0">Ajoutez des photos</span><div class="_3jk"><input id="js_l" aria-label="Ajoutez des photos à votre publication" multiple="" name="composer_photo" role="button" tabindex="0" class="_n _5f0v" data-reactid=".4.1.0.7.1.0.\$left.0.0.0.1" type="file"></div></a></div></div><a data-hover="tooltip" class="_3xem" aria-label="Ajoutez ce que vous faites ou votre humeur" tabindex="0" role="button" data-reactid=".4.1.0.7.1.0.\$left.0.2"><span class="accessible_elem" data-reactid=".4.1.0.7.1.0.\$left.0.2.0">Ajoutez ce que vous faites ou votre humeur</span><div class="_3xen _3vk5" data-reactid=".4.1.0.7.1.0.\$left.0.2.1"></div></a><a data-hover="tooltip" class="_3xem" aria-label="Ajoutez un lieu à votre publication" tabindex="0" role="button" data-reactid=".4.1.0.7.1.0.\$left.0.3"><span class="accessible_elem" data-reactid=".4.1.0.7.1.0.\$left.0.3.0">Identifier un lieu</span><div class="_3xen _52xx" data-reactid=".4.1.0.7.1.0.\$left.0.3.1"></div><noscript data-reactid=".4.1.0.7.1.0.\$left.0.3.2"></noscript></a><a data-hover="tooltip" class="_3xem" aria-label="Définir la date et l’heure de votre publication" tabindex="0" role="button" data-reactid=".4.1.0.7.1.0.\$left.0.4"><span class="accessible_elem" data-reactid=".4.1.0.7.1.0.\$left.0.4.0">Définir la date et l’heure de votre publication</span><div class="_3xen _2czx" data-reactid=".4.1.0.7.1.0.\$left.0.4.1"></div></a></div></div><div class="_ohf rfloat" data-reactid=".4.1.0.7.1.0.\$right"><div class="_2ph- _4-u3" data-reactid=".4.1.0.7.1.0.\$right.0"><button aria-label="Mettez votre publication en avant pour atteindre plus de monde" data-hover="tooltip" data-testid="boosted_post_button_with_id" class="_4dyi _4jy0 _4jy3 _517h _51sy _42ft" type="submit" value="1" data-reactid=".4.1.0.7.1.0.\$right.0.0:\$boosted_post_button"><span class="_4m40" data-reactid=".4.1.0.7.1.0.\$right.0.0:\$boosted_post_button.1">Mettre en avant</span></button><div class="_51xa" data-reactid=".4.1.0.7.1.0.\$right.0.2"><button class="_1mf7 _4jy0 _4jy3 _4jy1 _51sy selected _42ft" data-testid="react-composer-post-button" type="submit" value="1" data-reactid=".4.1.0.7.1.0.\$right.0.2.0"><span data-reactid=".4.1.0.7.1.0.\$right.0.2.0.1">Publier</span></button><div class="_lde uiPopover _6a _6b" data-reactid=".4.1.0.7.1.0.\$right.0.2.1"><button role="button" class="_p _4jy0 _4jy3 _4jy1 _51sy selected _42ft" type="submit" value="1" data-reactid=".4.1.0.7.1.0.\$right.0.2.1.\$/=10"><i class="img sp_5_FvgObiY-v sx_a9190d" data-reactid=".4.1.0.7.1.0.\$right.0.2.1.\$/=10.2"></i></button></div></div></div></div></div></div></div></div><noscript data-reactid=".4.1.1"></noscript><noscript data-reactid=".4.1.2"></noscript><noscript data-reactid=".4.1.\$QUESTION"></noscript><noscript data-reactid=".4.1.\$QANDA"></noscript></div></div>`; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; if ((m = regex.exec(str)) !== null) { // 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