devdocs/html/attributes%2Felementtiming.html


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<header><h1>HTML attribute: elementtiming</h1></header><div class="section-content">
<p>The <code>elementtiming</code> attribute is used to indicate that an element is flagged for tracking by <a href="https://developer.mozilla.org/en-US/docs/Web/API/PerformanceObserver"><code>PerformanceObserver</code></a> objects using the <code>"element"</code> type. For more details, see the <a href="https://developer.mozilla.org/en-US/docs/Web/API/PerformanceElementTiming"><code>PerformanceElementTiming</code></a> interface.</p> <p>This attribute may be applied to <a href="../element/img"><code>&lt;img&gt;</code></a>, <a href="https://developer.mozilla.org/en-US/docs/Web/SVG/Element/image"><code>&lt;image&gt;</code></a> elements inside an <a href="https://developer.mozilla.org/en-US/docs/Web/SVG/Element/svg"><code>&lt;svg&gt;</code></a>, poster images of <a href="../element/video"><code>&lt;video&gt;</code></a> elements, elements which have a <a href="https://developer.mozilla.org/en-US/docs/Web/CSS/background-image"><code>background-image</code></a>, and elements containing text nodes, such as a <a href="../element/p"><code>&lt;p&gt;</code></a>.</p> <p>In the DOM, this attribute is reflected as <a href="https://developer.mozilla.org/en-US/docs/Web/API/Element/elementTiming"><code>Element.elementTiming</code></a>.</p>
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<h2 id="usage">Usage</h2>
<div class="section-content">
<p>The value given for <code>elementtiming</code> becomes an identifier for the observed element.</p> <div class="code-example">
<p class="example-header"><span class="language-name">html</span></p>
<pre data-signature="w87uhoL1QZvo2KwrTNuXDIr4E9WacRy37Vr05EEFP1o=" data-language="html"><span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>img</span> <span class="token attr-name">alt</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>alt<span class="token punctuation">"</span></span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>img.jpg<span class="token punctuation">"</span></span> <span class="token attr-name">elementtiming</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>label for element<span class="token punctuation">"</span></span> <span class="token punctuation">/&gt;</span></span>
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</div> <p>Good contenders for elements you might want to observe are:</p> <ul> <li>The main image for an article.</li> <li>A blog post title</li> <li>Images in a carousel for a shopping site.</li> <li>The poster image for the main video on a page.</li> </ul>
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<h2 id="examples">Examples</h2>
<div class="section-content"><div class="code-example">
<p class="example-header"><span class="language-name">html</span></p>
<pre data-signature="YX9Ph3kJBCGuX2XRXVEKuZTv4qBwpwoXKEAsTW3eKeE=" data-language="html"><span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>img</span> <span class="token attr-name">alt</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>Alt for a main blog post image<span class="token punctuation">"</span></span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>my-massive-image.jpg<span class="token punctuation">"</span></span> <span class="token attr-name">elementtiming</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>Main image<span class="token punctuation">"</span></span><span class="token punctuation">&gt;</span></span>

<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>p</span> <span class="token attr-name">elementtiming</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">"</span>important-text<span class="token punctuation">"</span></span><span class="token punctuation">&gt;</span></span>Some very important information.<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>p"</span><span class="token punctuation">&gt;</span></span>
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<h2 id="see_also">See also</h2>
<div class="section-content"><ul> <li><a href="https://developer.mozilla.org/en-US/docs/Web/API/PerformanceElementTiming"><code>PerformanceElementTiming</code></a></li> <li><a href="https://developer.mozilla.org/en-US/docs/Web/API/Element/elementTiming"><code>Element.elementTiming</code></a></li> </ul></div><div class="_attribution">
  <p class="_attribution-p">
    &copy; 2005&ndash;2023 MDN contributors.<br>Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.<br>
    <a href="https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/elementtiming" class="_attribution-link">https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/elementtiming</a>
  </p>
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