 <p>I had a similar problem recently, specifically making the width match the parent div and also respond. I couldn't work out why Trust Pilot thought it appropriate to set something to make the height of the frame dynamic and not the width, but anyway.</p> <p>Firstly, I had some CSS for the parent div, like:</p> <pre><code>&lt;style type="text/css"&gt; div.trust-pilot{ width: 100% !important; height: auto; } &lt;/style&gt; </code></pre> <p>This may not actually be necessary, but I put it there anyway.</p> <p>These are the 'trustbox' settings I used (see <a href="http://trustpilot.github.io/developers/#trustbox" rel="nofollow">http://trustpilot.github.io/developers/#trustbox</a>):</p> <pre><code>&lt;div id="trust-pilot" class="trust-pilot"&gt; &lt;div class="tp_-_box" data-tp-settings="domainId: xxxxxxx, bgColor: F5F5F5, showRatingText: False, showComplementaryText: False, showUserImage: False, showDate: False, width: -1, numOfReviews: 6, useDynamicHeight: False, height: 348 "&gt; &lt;/div&gt; &lt;script type="text/javascript"&gt; (function () { var a = "https:" == document.location.protocol ? "https://ssl.trustpilot.com" : "http://s.trustpilot.com", b = document.createElement("script"); b.type = "text/javascript"; b.async = true; b.src = a + "/tpelements/tp_elements_all.js"; var c = document.getElementsByTagName("script")[0]; c.parentNode.insertBefore(b, c) })(); &lt;/script&gt; &lt;/div&gt; </code></pre> <p>Replace the domainId with something valid (in the case of this question, it's 3660907). Note that the width: -1 parameter might work already for you except if you want the page to be responsive (that is below).</p> <p>Firstly, to make the width match the parent div, I used:</p> <pre><code>&lt;script type="text/javascript"&gt; jQuery( window ).load(function() { _width = jQuery('#trust-pilot').innerWidth(); jQuery('#tpiframe-box0').attr('width',_width); }); &lt;/script&gt; </code></pre> <p>And then to make the box respond, I used:</p> <pre><code>&lt;script type="text/javascript"&gt; jQuery( window ).resize(function() { _width = jQuery('#trust-pilot').innerWidth(); jQuery('#tpiframe-box0').attr('width',_width); }); &lt;/script&gt; </code></pre> <p>I hope that this helps. Shaun.</p>