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How Browsers Really Parse HTML (and What That Means for SEO)

February 26, 2026 · 33 min

Show notes

Martin and Gary unpack how HTML parsing really works, why the HTML standard is so lenient, and how messy markup can silently break key SEO signals like hreflang and rel=canonical. They revisit validators and cross‑browser hacks from the Netscape/IE days, and discuss whether semantic HTML and strict validity truly matter for search. You'll also hear when link hints like preload, prefetch, and DNS prefetch help performance (and indirectly SEO), and where meta and link tags really belong.

​ Resources:

HTML Living Standard → https://html.spec.whatwg.org/

Episode transcript → https://goo.gle/sotr105-transcript

Listen to more Search Off the Record → https://goo.gle/sotr-yt Subscribe to Google Search Channel → https://goo.gle/SearchCentral

Search Off the Record is a podcast series that takes you behind the scenes of Google Search with the Search Relations team.

#SOTRpodcast #SEO #GoogleSearch

Speakers: Martin Splitt, Gary Illyes

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