Technical SEO: The Complete Reference

Googlebot has a finite budget for your site. Waste it and important pages go uncrawled. - robots.txt — check what you're blocking, and confirm your CDN isn't blocking more - XML sitemaps — include only indexable, canonical URLs; a sitemap full of redirects and 404s reduces trust in the whole file - Internal linking — orphaned pages with no internal links are frequently never found - Crawl traps — faceted navigation, calendars and session parameters can generate effectively infinite URLs

Being crawled isn't being indexed. - Canonical tags — every page should self-reference unless deliberately consolidating - noindex usage — audit what's excluded; accidental noindex on template-level pages is common and catastrophic - Duplicate content — parameter URLs, print versions, staging environments left crawlable - Thin pages — pages with no genuine value dilute site quality signals

• [+]Core Web Vitals — LCP (loading), INP (interactivity), CLS (visual stability)
• [+]JavaScript rendering — verify what Googlebot actually sees; client-side-only content is a frequent, invisible failure
• [+]Image delivery — modern formats, correct sizing, lazy loading below the fold
• [+]Third-party scripts — usually the largest single performance cost on established sites

• [+]Organization sitewide, Service on service pages, LocalBusiness on location pages
• [+]FAQPage wherever genuine Q&A exists
• [+]Article with named authorship on guides and research Structured data helps both classic rich results and AI extraction — see our GEO guide.

If you serve more than one country, hreflang is technical SEO's highest-stakes area. See our dedicated hreflang guide.

Technical SEO regresses. Every deploy is a chance to reintroduce a fixed problem. Ongoing monitoring — index coverage, Core Web Vitals, crawl stats — is what keeps gains permanent.