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Analytics

VWO in Homepage Source

VWO (Visual Website Optimizer) is an A/B testing, heatmap and conversion-optimization suite aimed at marketing and growth teams.

The source-code fingerprint

The account library loads from dev.visualwebsiteoptimizer.com/j.php, so that host appears in a script tag alongside the account ID; the inline _vwo_code snippet is an alternative marker.

Likely false positives: The async loader is often present with no campaign running; read a match as 'VWO installed', not 'test active'.

Stored source examples for VWO

These examples matched dev.visualwebsiteoptimizer.com in stored homepage source when the query was sampled on 2026-10-14. The sites may have changed since the source was captured. A match establishes a source reference; it does not confirm an active installation or code execution.

• www.forbes.com ...r n = this.getCombinationCookie();\n\t\t\t\t\t\tthis.load('https://dev.visualwebsiteoptimizer.com/j.php?a=' + account_id + '&u=' + encodeURIComponent(d.URL) ...
• www.weforum.org ...ld(d.createTextNode(b));h.appendChild(a);this.load('https://dev.visualwebsiteoptimizer.com/j.php?a='+account_id+'&u='+encodeURIComponent(d.URL)+'&f='+...
• www.ted.com ...s/gpt.js" as="script"/><link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com"/><link rel="preconnect" href="https://sli.ted.com" crossor...
• www.uber.com ...om eu.srv.stackadapt.com https://bzr.openai.com/v1/ https://dev.visualwebsiteoptimizer.com/j.php https://accounts.google.com https://auth.uber.com htt...
• foursquare.com ...O Async SmartCode -->\r\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\r\n<script type='text/plain' id='vwoCode' class="optanon-...
• searchengineland.com ... Async SmartCode -->\n\t\t<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n\t\t<script type='text/javascript' id='vwoCode'>\n\t\twindow...
• www.oecd.org ...ensearch.xml"/>\n\n\n\n <link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com/"/>\n <script type='text/javascript' id='vwoCode'>\n\n ...
• www.merriam-webster.com ...WO Async SmartCode -->\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n<script type='text/javascript' id='vwoCode'>\nwindow._vw...
• www.upwork.com .../"><link data-n-head="ssr" rel="dns-prefetch" href="https://dev.visualwebsiteoptimizer.com/"><script data-n-head="ssr" type="application/ld+json">{"@c...
• www.constantcontact.com ...images.ctfassets.net"/><link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com"/><link rel="preconnect" href="https://logx.optimizely.com"...
• www.britannica.com ...</script>\n\n\n\n \n\n <link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n<script type='text/javascript' id='vwoCode'>\n window...
• www.qualtrics.com ...c V3.0 SmartCode -->\n <link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n <script type="text/javascript" id="vwoCode">\n window...
• www.oreilly.com ...O Async SmartCode -->\r\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\r\n<script type='text/javascript' id='vwoCode'>\r\nwindow._...
• stability.ai ...WO Async SmartCode -->\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n<script type='text/javascript' id='vwoCode'>\nwindow._vw...
• www.checkpoint.com ... Async SmartCode -->\n <link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" class="optanon-category-C0002" />\n <script type='text/jav...
• www.taboola.com ...O Async SmartCode -->\n\t<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n\t<script type='text/javascript' id='vwoCode'>\n\t\twindow....
• www.cognitoforms.com ...VWO Async SmartCode --><link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com"><script type="text/javascript" id="vwoCode">\n\t\twindow._vwo...
• www.kobo.com ...licy="no-referrer-when-downgrade" id="vwoCode" src="https://dev.visualwebsiteoptimizer.com/lib/778105.js"></script><script src="/_next/static/chunks/p...
• teachable.com ...WO Async SmartCode -->\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n<script type='text/javascript' id='vwoCode'>\nwindow._vw...
• www.myfonts.com ... Async SmartCode -->\n <link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n <script type='text/javascript' id='vwoCode'>\n window...
• www.moma.org ...912};\n </script>\n\n \n\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n<script type='text/javascript' id='vwoCode'>\nwindow._vw...
• www.appsflyer.com ... var c=this.getCombinationCookie();this.load("https://dev.visualwebsiteoptimizer.com/j.php?a="+account_id+"&u="+encodeURIComponent(d.URL)+"&f="+...
• www.backblaze.com ...for backblaze.com -->\n\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n<script>\n function vwo() {\n window._vwo_code || (fu...
• www.techopedia.com ...O Async SmartCode -->\n\t<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n\t<script data-cfasync="false" nowprocket type='text/jav...
• www.aweber.com ...WO Async SmartCode -->\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com">\n<script type="text/javascript" id="vwoCode">\nwindow._vwo_...
• convertkit.com ...ild(e);var n=this.getCombinationCookie();this.load('https://dev.visualwebsiteoptimizer.com/j.php?a='+account_id+'&u='+encodeURIComponent(d.URL)+'&f='+...
• www.webfx.com ...nc SmartCode -->\n <link rel="dns-prefetch" href="https://dev.visualwebsiteoptimizer.com" />\n <script type="text/javascript" id="vwoCode">\n wi...
• www.business2community.com ...O Async SmartCode -->\n\t<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com" />\n\t<script data-cfasync="false" nowprocket type='text/jav...
• wp-rocket.me ...WO Async SmartCode -->\n<link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com"/>\n<!-- IMPORTANT: data-cfasync="false" must be preserved o...
• www.dashlane.com ...th" data-next-head=""/><link rel="preconnect" href="https://dev.visualwebsiteoptimizer.com"/><style type="text/css">@font-face {font-family:'Public Sa...

Showing 30 checked source examples. The headline is estimated matches. Open the full ranked list, inspect the matched source, and export the domain list →

Related technologies

How this works

The headline distinguishes candidate upper bounds (index prefilter), estimated matches (a projection from checked samples) and verified matches (an exact count established by the engine). The index contains 131,219,565 homepage documents, one homepage per hostname, including subdomains. The source index was promoted 2026-09-22 and follows a quarterly rebuild schedule. The sample date is when this query was checked against the stored index, not a new crawl of each example site.

Comparing adoption across tools? The Web Technology Adoption Report ranks the most common tags in the index side by side.