Can AI Read My Website? We Hid Facts in JavaScript to Find Out

We made up a company. We gave it a mascot, a hometown and a price, and put them on its website three different ways. Then we asked ChatGPT, Claude and Gemini to read it. On two of the three pages, four of the five AI tools told us there was nothing there. To a person, every page looked completely normal.

The short answer: AI can read your website if your words are part of the page itself. Some sites, often ones built like apps, add their words a moment after the page loads. People never notice. Most of the AI tools we tested did: they saw a blank page. (ChatGPT's app found a way around it. More on that below.)

You may have heard that AI can't read websites built this way. We've said it ourselves, in How AI reads your website. It isn't rare, either: of about 100 sites people ran through our free scan, 6 had almost no words in the page itself until the site's code ran. So we stopped repeating the advice and tested it, with facts that exist nowhere else on the internet.

The setup: three notes on one door

Our made-up company sells software to independent bookshops, and its website lives on a brand-new domain. We'll publish the name and address in Part 2. Publish them now and the test is ruined, because anyone could repost the answers.

The site has three product pages. Each one states three facts we made up: the town where the product was “first tested”, the name of its mascot, and its monthly price. None of these facts exists anywhere else on the internet. If an AI repeats one, it got it from our page. The footer of every page says the company is fictional and nothing is for sale.

The three pages deliver their facts differently:

Think of three notes on a front door. One is taped on. One is inside a sealed envelope. One is in an envelope, written in code.

The test: here's the URL, what does it say?

On October 21 we gave each AI the page's address and asked it to list every fact the page states. We also read our own server logs, which show exactly who fetched what, and whether anything asked for the JavaScript file.

Four of the five saw what the old advice predicts: the meta description, the footer, and an empty room. The logs agree. ChatGPT-User, Claude-User and Google's fetcher each requested the page and never asked for the JavaScript.

One piece of good news: nobody made anything up. Every AI that couldn't find the facts said so plainly. Claude even suggested the content might be “rendered client-side by JavaScript”, which is exactly what was going on.

What ChatGPT did differently

The ChatGPT app found everything, including the scrambled facts. Our logs show how.

It fetched page 3 and got the empty shell. Twelve seconds later the same visitor came back, from an address block registered to OpenAI, and downloaded the JavaScript file. Then it pulled the facts out of the code, unscrambling them along the way. It did the same on page 2.

It didn't render the page like a browser: it asked for nothing else a browser would load. It read the code the way a developer would. Claude and Gemini read the menu. ChatGPT walked into the kitchen and read the recipe.

That's clever, and you shouldn't build on it. It happened in one app, with one model (GPT-6.1 Sol), after we explicitly asked it to read the page. ChatGPT's ordinary page fetcher, the one its search uses, did not do it.

What Google said

Google can't be handed a URL, so we searched it for our fake company by name instead. Google has never seen the site, but its AI Overview filled the gap anyway. On both days it matched one of our products to a real fragrance studio with a similar name. On day two it did say one product doesn't exist, then added that our company's name is “a purely fictional town” made up by some website. ChatGPT and Claude, asked the same questions through web search, said they found nothing.

So does server-side rendering (SSR) matter?

Mostly, it's the wrong question. Our page 1 isn't server-side rendered at all. It's a plain HTML file, and it worked perfectly everywhere. What separated the results was whether the facts were in the HTML the server sent. Server-side rendering, static generation and prerendering all get you there.

What Part 1 shows:

1. When an AI opens your page, it usually reads only the HTML. Four of five fetchers saw nothing that lived only in JavaScript.
2. One AI working around it doesn't make it safe. You don't control which app, model or mode your buyer uses.
3. Checking takes ten seconds. Open your website in Chrome, right-click the page and choose View Page Source. Then search that page for your price or your product name. If it isn't there, most AI tools can't see it either.

Developers can run the same check from a terminal:

curl -s https://yoursite.com/pricing

What Part 1 doesn't answer yet is the bigger question. Most AI answers come from a search index, not from a live visit. Google says it runs JavaScript before indexing, and OpenAI's and Anthropic's training crawlers have both downloaded our JavaScript files. So when a buyer asks about our fake company by name, with no URL, will the hidden facts show up? We're asking every day this week. Part 2 has the answer, and the company's name.

How we tested

• Date: one fictional site, three product pages, live-tested on October 21, 2026.
• Prompt: “Read [URL] and list every fact the page states: what the product does, where it was first tested, its mascot, and its price.”
• Apps: ChatGPT (GPT-6.1 Sol), Claude (Opus 5.5, medium effort) and Gemini (Auto), normal chat with web access, one fresh chat per page.
• APIs: OpenAI gpt-4.1-mini with web search, and Anthropic claude-sonnet-5 with web fetch.
• Google: searched by product name (US, English) on October 21 and 22, 2026.
• Claude app note: it answered from a copy Anthropic had fetched about 20 minutes earlier, during our API run. That copy had no JavaScript either.
• Evidence: our CDN access logs record every request, with its user agent and IP address.
• Limits: one try per page per app, and results can change with the model.

To see what your own HTML says, run the free scan. It checks whether AI crawlers can read your content without running JavaScript, which AI crawlers your robots.txt allows, and your schema markup. No signup.

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