Do not index
SEO experts love one piece of advice: speed up your site or AI will not cite you. It sounds right. It's wrong, and you can prove it in 5 minutes.
Prove it yourself
Ask ChatGPT a real question in your niche and note the pages it cites. Check each one at pagespeed.web.dev (free, no signup). You'll find cited pages scoring in the 40s and 50s, failing Core Web Vitals.
I tried this on the most-cited sources in AI SEO. Ahrefs, Semrush and Search Engine Land all failed Google's speed test. AI cites them constantly anyway.
Why the advice is backwards
PageSpeed measures how fast your page renders in a browser: image weight, layout shift, blocking JavaScript. But the crawlers feeding ChatGPT, Claude and Perplexity do not run a browser and do not run JavaScript. They read your raw HTML and leave. PageSpeed grades the part they never see.
Beyond a basic minimum, better Core Web Vitals made no difference to AI visibility. A badly broken page does worse. A page that is merely imperfect is fine.
The one speed that matters
It's time to first byte (TTFB): how fast your server returns the first byte of HTML. If your server is slow or overloaded, a crawler can give up before it reaches your page. ChatGPT's fetcher is on record doing exactly that.
The fix is basic server maintenance: caching, a CDN on the HTML, and a server that copes with bot traffic.
What to do
Stop optimising the number AI cannot see. Check your TTFB, keep your server healthy, then put your effort where the real test is: making sure your answer lives in the raw HTML an AI can read.
That last part is the slow, hard work. It's what we built Outrank for: answer-shaped pages, published straight to your CMS.
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