Quick answer: technical SEO makes sure search engines and AI crawlers can find, crawl, render, understand and trust your pages. The most important checks are: pages are indexable, the sitemap and robots.txt are correct, each page has one canonical URL, the site is fast and mobile-friendly, there are no broken links or redirect chains, and structured data describes your business and content correctly.

Work through the 25 checks below with Google Search Console and a free crawler such as Screaming Frog (free up to 500 URLs) open.

Crawling and indexing

  1. Your important pages are indexed. In Search Console's Pages report, check that service pages, key landing pages and blog posts are indexed, and read the reasons for excluded pages.
  2. robots.txt is not blocking anything important. Visit yoursite.com/robots.txt. Make sure it does not disallow your content, CSS or JavaScript.
  3. An XML sitemap exists and is submitted. It should list only canonical, indexable pages that return a 200 status, and be submitted in Search Console and Bing Webmaster Tools.
  4. No accidental noindex tags. A leftover noindex from a staging site can hide your whole website. Check the page source of key pages for noindex.
  5. Canonical tags point to the right URL. Each page should have a self-referencing canonical, and duplicates should point to the main version.
  6. One version of your domain. http/https and www/non-www versions should all redirect to one preferred version.
  7. Important pages are within three clicks of the homepage. Deeply buried pages get crawled less often.
  8. No orphan pages. Every page you want ranked should have internal links pointing to it.

Status codes and redirects

  1. No broken internal links (404s). Fix the links or redirect the old URLs.
  2. No redirect chains or loops. Each old URL should redirect once, directly to the final page.
  3. Permanent moves use 301 redirects. Temporary 302s for permanent changes send mixed signals.
  4. Server errors (5xx) are rare. Frequent errors reduce crawling and frustrate visitors.
Work through the list one check at a time. Photo by Jakub Żerdzicki on Unsplash
Work through the list one check at a time. Photo by Jakub Żerdzicki on Unsplash

Speed and mobile

  1. Core Web Vitals pass on mobile. Check the Core Web Vitals report in Search Console and PageSpeed Insights. Learn what the metrics mean in Core Web Vitals explained.
  2. Images are compressed and sized correctly. Use WebP or AVIF, set width and height, and lazy-load images below the fold.
  3. Unused scripts and plugins are removed. Every chat widget, tracker and slider adds weight.
  4. The site works well on phones. Text is readable without zooming, buttons are easy to tap and nothing overflows the screen.
  5. Caching and compression are enabled. Use browser caching, Gzip or Brotli compression, and a CDN where useful.

On-page structure

  1. Every page has a unique, descriptive title tag. Duplicate or missing titles are common on templated sites.
  2. Every page has a meta description. It does not directly affect rankings, but it affects clicks.
  3. One H1 per page, with a logical heading structure. H2s and H3s should outline the content like a table of contents.
  4. Images have useful alt text. Describe the image for people who cannot see it.
  5. URLs are short, readable and stable. Use words, not IDs, and avoid changing them without redirects.

Structured data and AI readiness

  1. Organization (or LocalBusiness) schema is in place, with your name, logo, contact details and links to your official profiles. Add Service, Article, Product, FAQPage and BreadcrumbList schema where they fit, and validate with Google's Rich Results Test.
  2. AI crawlers are not blocked by accident. If you want to appear in AI answers, check that robots.txt does not block crawlers such as OAI-SearchBot, PerplexityBot or Google-Extended unless that is your intention.
  3. Content is in the HTML. Important text should not only appear after heavy JavaScript runs or inside images. Search engines and many AI crawlers read HTML most reliably.

For the AI side of technical SEO, read llms.txt, schema and entities.

How often should you run a technical SEO audit?

Run a full audit at least twice a year, and always before and after a redesign, platform migration or major content change. Check Search Console monthly for new indexing or Core Web Vitals issues.

How to prioritize fixes

Not every issue matters equally. Fix in this order:

  1. Anything that stops important pages being indexed (noindex, robots.txt, server errors)
  2. Problems affecting many pages at once (templates, redirects, site speed)
  3. Issues on your highest-value pages (services, top landing pages)
  4. Everything else

Frequently asked questions

What is technical SEO?

Technical SEO is the part of SEO that makes sure search engines can crawl, render, index and understand your website. It covers site speed, mobile usability, indexing, redirects, site structure and structured data.

Can technical SEO problems stop my site from ranking?

Yes. A noindex tag, a blocking robots.txt rule or broken redirects can stop pages from ranking no matter how good the content is.

Do I need a developer for technical SEO?

Some checks you can do yourself in Search Console. Fixes involving templates, server settings, redirects or site speed usually need a developer.

Want an expert to run these 25 checks for you? Our SEO service starts with a technical audit, and the free website audit highlights your most urgent issues.

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