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Technical SEO

What is technical SEO?

Short answer

Technical SEO is the work that lets search engines and AI crawlers find, crawl, render and index your pages, and understand how they relate. It covers site architecture, internal links, robots.txt, sitemaps, canonical tags, redirects, page speed, mobile usability, structured data and JavaScript rendering. Without it, good content may never be seen.

The full answer

Content and links decide how well a page can rank; technical SEO decides whether it can compete at all. The main areas are:

  • Crawling: robots.txt rules, server errors, redirect chains and crawl traps such as endless filter URLs.
  • Indexing: noindex tags, canonical tags, duplicate content and thin pages.
  • Rendering: whether important content and links appear in the HTML or only after JavaScript runs.
  • Architecture: a logical hierarchy, internal links to important pages and clean URLs.
  • Performance: Core Web Vitals and the mobile experience.
  • Structured data: markup that accurately describes what's on the page.
  • International setup: hreflang for sites with several languages or regions.

Technical SEO affects AI visibility too. Many AI crawlers fetch HTML without running JavaScript, and firewalls sometimes block them, so a site that works for Googlebot can still be unreadable to ChatGPT or Perplexity.

A technical audit finds and prioritises these issues by impact, so developers fix the problems affecting the most important pages and templates first.

Published by Vidern, founded and led by Malhar Shah. Updated .

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