Technical SEO Checklist: 30 Checks for Your Website in 2026

Technical SEO makes sure search engines can find, crawl, render and understand your pages. If it's broken, great content won't rank. This checklist is the one we use when auditing websites, grouped by area.

Crawling and indexing

1. robots.txt doesn't block important pages, CSS or JavaScript. Guide: robots.txt explained.
2. An XML sitemap exists, lists only live, indexable URLs, and is submitted in Search Console. Guide: XML sitemaps.
3. No important pages carry a noindex tag by accident, a common leftover from staging sites.
4. The Page indexing report in Search Console has been reviewed and errors explained. Guide: fixing indexing issues.
5. Staging and test sites are not indexed. Password-protect them.
6. Orphan pages, with no internal links pointing to them, are linked or removed.

URLs and duplicates

1. One version of the site: http to https and www to non-www, or the reverse, redirect to a single version.
2. Canonical tags point to the preferred URL on every page. Guide: canonical tags.
3. Trailing slash handling is consistent.
4. URL parameters like sorting and tracking don't create indexable duplicates.
5. URLs are readable: /services/local-seo, not /index.php?id=42.

Redirects and errors

1. No redirect chains of three or more hops.
2. Old URLs redirect with 301s to their closest equivalent after any redesign. Guide: website migration checklist.
3. Broken internal links are fixed.
4. The 404 page returns a real 404 status, not a 200 ("soft 404").

Speed and Core Web Vitals

1. LCP under 2.5 seconds for most real users. Guide: Core Web Vitals explained.
2. INP under 200 milliseconds.
3. CLS under 0.1.
4. Images compressed, in WebP or AVIF, with width and height set.
5. Text compression (gzip or Brotli) and caching enabled.
6. Server response time is fast. Check where you're hosted. Guide: hosting and SEO in Sri Lanka.

Mobile

1. A responsive design with a viewport meta tag.
2. Tap targets are large enough, and text is readable without zooming.
3. Content is the same on mobile and desktop. Google indexes the mobile version.

Security

1. HTTPS on every page, with a valid certificate and no mixed content. Guide: HTTPS and SEO.
2. Security headers like HSTS are in place.

Rendering and structured data

1. Key content is in the HTML, or renders reliably for Google. Guide: JavaScript SEO.
2. Structured data is valid for your organisation, services, products or articles. Guide: structured data.

International and language

1. hreflang is correct if you have Sinhala, Tamil or other language versions. Guide: Sinhala and Tamil SEO.

Monitoring

1. Search Console and GA4 are set up, and someone checks them monthly.

Where to start

You can check several of these items in 30 seconds with our free SEO health check. For a full audit of all 30, with fixes made for you, see our technical SEO service.