RenderFox: AI Crawler Render Gap

See your page the way ChatGPT, Claude and Perplexity see it, with every piece of text they miss boxed in red.

See your page the way ChatGPT, Claude and Perplexity see it, with everything they miss boxed in red. ChatGPT, Claude and Perplexity don't run JavaScript, so anything your page builds in the browser never reaches them. RenderFox asks for your page the way their crawlers do, sets what comes back beside the page you're looking at, and puts a red box around every piece of text they didn't get. It's free, there's no account, and your pages stay in your browser. WHY IT MATTERS Your browser downloads a page, runs its JavaScript and shows you the finished result. The live fetchers behind ChatGPT, Claude and Perplexity stop after the download. If your prices, product names, reviews or FAQs are added by JavaScript, the assistant answers as if they weren't on the page. You'd never spot it yourself, because your browser always finishes the job. HOW IT WORKS Open any page and click the fox. RenderFox checks ChatGPT, Claude and Perplexity straight away and gives you one plain sentence for each, such as "ChatGPT misses a lot of this page. It gets 52% of the text you can see." Click "See what ChatGPT sees" for the full report. WHAT YOU GET • A plain answer for each assistant, with the share of your visible text it gets. • Your page beside the crawler's copy, scrolling together, and a slider to sweep from one to the other. • Every missing piece boxed in red and listed, so you can step through them or jump straight to one. • Nine crawlers in one report, from the live fetchers behind ChatGPT, Claude and Perplexity to the search crawlers from OpenAI and Perplexity, the training crawlers from OpenAI and Anthropic, Googlebot, and Chrome with JavaScript switched off. • A warning when a crawler gets a different main headline from the one on your screen. • The real page a crawler was given when a site turns it away or shows it a bot check, because blocked isn't the same as missing. • Cookie pop-ups and chat windows left out of the score, since a vendor's script adds them and they aren't your content. GOOD TO KNOW RenderFox sends the same kind of request a crawler does, under that crawler's published name and without your cookies, but it comes from your computer. A site that checks where crawlers really come from can answer differently, and RenderFox tells you when bot protection steps in. PRIVACY RenderFox has no server. It reads only the tab you click it on, asks that site for the same page, and shows you the difference, all inside Chrome. It saves nothing and sends nothing to me. The full policy is at tryrenderfox.com/privacy. WHO IT'S FOR SEO and GEO practitioners, developers working on JavaScript sites, and content teams and agencies who want to know whether AI assistants can read their pages. Built by Suganthan Mohanadasan, who also makes FanoutFox. RenderFox isn't affiliated with OpenAI, Anthropic, Perplexity or Google.