Technical SEO is invisible when it works and expensive when it does not. These are the checks I run on every site, in the order that matters.

Crawling

  • Robots file is reachable, valid and not blocking anything important
  • An XML sitemap exists, is valid and is referenced from robots.txt
  • No accidental noindex on pages you want ranked
  • Unknown URLs return a real 404 status, not a soft 404 served as 200
  • Important pages are reachable within three clicks of the home page

The soft 404 check catches more sites than any other item on this list. If a wrong URL quietly returns the home page with a 200 status, crawlers waste budget and users get confused.

Rendering

  • Core content is present in the initial HTML, not only injected by JavaScript
  • No render-blocking resources in the document head
  • Mobile layout parity with desktop, including hidden content
  • Fonts load without causing layout shift

Indexing

  • Canonical tags point to the correct URL on every page
  • Pagination uses real, crawlable links with rel next and previous
  • Old URLs redirect with a single 301 hop, not a chain
  • Duplicate versions resolve to one canonical version
  • Faceted or filtered URLs are handled deliberately, not left open

Speed

  • Images compressed and served at the size they are displayed
  • Caching headers set for static assets
  • Server response time under two hundred milliseconds
  • Text compression enabled for HTML, CSS and JavaScript

Structured data

Add the schema that matches each page type: ProfessionalService or LocalBusiness for the home page, Service for service pages, Article for blog posts, and BreadcrumbList for navigation. Validate it, and keep it consistent with what is actually visible on the page.

Monitoring that actually helps

Connect a search console account and review the coverage report monthly. Set alerts on sudden drops in impressions rather than waiting for a ranking report to notice, because a deindexing problem found in week one costs far less than one found in month two.

Finally, keep a simple change log. When traffic moves, the first question is always what changed on the site, and a log answers it in seconds.