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1 in 20 Danish corporate websites are effectively invisible to ChatGPT
2026-07-21 · Martin Nymann · 5 min reading
AI crawlers do not run JavaScript. Of the 465 sites scanned, 22 had virtually no readable text without JavaScript — their content exists, but the AI cannot see it.
AI crawlers do not run JavaScript. Of 465 Danish company websites scanned on 21 July 2026, 22 sites (5 per cent) had virtually no readable text when JavaScript was not running — their content exists, but ChatGPT, Claude and Perplexity cannot see it. A further 38 sites (8 per cent) had fewer than 150 words.
Why don’t AI crawlers run JavaScript?
Because it is too expensive on a large scale. Running JavaScript requires the crawler to launch a browser for every single page. Googlebot does this (with a delay), but GPTBot, ClaudeBot and PerplexityBot generally only fetch the raw HTML. If your content isn’t in that, it doesn’t exist for them.
What does an invisible page look like?
A human sees a complete homepage with services, prices and contact details. An AI crawler sees this:
That’s the whole page. Everything else is loaded via JavaScript after the page has loaded — and that step never happens for the crawler.
Which sites are affected?
Typically, sites built as client-side rendered apps: React, Vue and Angular without server-side rendering, as well as some pages from modern site builders. In our sample, the legal sector is hardest hit, with 16% of sites having fewer than 150 words, compared with 7% for accountants and 5% for plumbers — see the sector ranking.
Can it be fixed?
Yes, and it rarely requires a new website. The usual approaches are server-side rendering (SSR), pre-rendering the most important pages, or embedding the core content — services, address, contact details — directly in the HTML rather than fetching it via JavaScript. Which approach is right depends on the platform.
The first step is to measure it. You cannot see the problem in your own browser, as your browser runs JavaScript.
This article is based on the same dataset as our main analysis of 465 Danish corporate websites, where you’ll find the full methodology and all the figures.
Method
Data was collected by Geoa on 21 July 2026. We fetched the homepage of 465 Danish corporate websites without running JavaScript — exactly as GPTBot, ClaudeBot and PerplexityBot do — and measured six technical signals: readable text, llms.txt, robots.txt access for AI crawlers, structured data (schema.org), H1 heading and meta description. The breakdown is 200 plumbing firms, 147 accountants/bookkeepers and 118 solicitors.
Important caveat: the sample consists of search-visible businesses — those that rank in local searches — not a random cross-section of the industry. The figures therefore describe the industry’s most visible businesses. A representative sample would, in all likelihood, look worse, not better. We therefore consistently write ‘of those scanned’, not ‘of all Danish’.
Frequently asked questions
How many websites are invisible to ChatGPT?
Of 465 Danish company websites scanned (Geoa, 21 July 2026), 22 sites — 5 per cent — had virtually no readable text when JavaScript was not run. A further 38 sites had fewer than 150 words. Their content exists, but AI crawlers cannot see it.
Why do AI crawlers not run JavaScript?
Because it is too expensive at scale. Running JavaScript requires the crawler to start a browser for every single page. GPTBot, ClaudeBot and PerplexityBot fetch only the raw HTML by default, so if your content is not in it, it does not exist for them.
How do I make my website readable for AI?
The usual routes are server-side rendering (SSR), prerendering the most important pages, or putting the core content — services, address and contact details — directly into the HTML instead of fetching it with JavaScript. Which route is right depends on the platform. The first step is to measure it, because you cannot see the problem in your own browser, which does run JavaScript.
How does your own website fare?
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