Technical SEO checklist for 2026

A technical SEO checklist for 2026 covers six areas: search engines can crawl your important pages, those pages get indexed, the site structure is clear, pages load fast and pass Core Web Vitals, content renders without relying on fragile JavaScript, and structured data plus AI crawler rules are set on purpose. Fix critical blockers first.

How to use this checklist

Work through it in order. Each section builds on the one before: there is no point optimizing page speed on pages Google cannot crawl. For each item, mark it as passing, failing or not applicable. Prioritize failures that affect your most important pages, usually your homepage, service or product pages, and top-traffic articles.

Tools you will need:

• Google Search Console, which is free and shows how Google sees your site.
• A site crawler, such as Screaming Frog SEO Spider or a similar tool.
• PageSpeed Insights, which is free and reports Core Web Vitals data.
• Bing Webmaster Tools, which is free and covers Bing, which also feeds some AI search products.

1. Crawling

Search engines must be able to reach your pages.

• robots.txt exists at the root, is valid, and does not block important sections, CSS or JavaScript files.
• No accidental site-wide disallow left over from a staging environment.
• XML sitemap exists, lists only canonical, indexable URLs that return a 200 status, and is submitted in Search Console and Bing Webmaster Tools.
• Sitemap updates automatically when pages are added or removed.
• Important pages are reachable through internal links, not only through the sitemap.
• Server responds reliably. Check Search Console's crawl stats report for errors and slow responses.

2. Indexing

Pages that are crawled must also be indexable and chosen for the index.

• Important pages do not carry a noindex tag by mistake.
• Each page has a self-referencing canonical tag, or a canonical pointing to the preferred version.
• Duplicate versions are consolidated: http and https, www and non-www, trailing slash variants, and URL parameters.
• Search Console's page indexing report has been reviewed, and reasons for unindexed important pages are understood.
• Thin, duplicate or low-value pages are improved, merged, or set to noindex.
• Pagination and filtered pages are handled so they do not create endless near-duplicate URLs.

3. Site structure and URLs

A clear structure helps search engines understand what matters.

• Important pages are within a few clicks of the homepage.
• URLs are short, readable and use hyphens between words.
• Navigation reflects your main topics and services.
• Internal links use descriptive anchor text.
• No orphan pages, meaning pages with no internal links pointing to them.
• Breadcrumbs are used on deeper sites.

For a deeper look at linking, see our internal linking strategy.

4. Status codes and redirects

• No internal links point to 404 pages.
• Removed pages with value or backlinks redirect with a 301 to the most relevant live page.
• No redirect chains or loops. Each redirect goes directly to the final URL.
• Soft 404s, where a missing page returns a 200 status, are fixed.
• The site serves over HTTPS with a valid certificate, and http redirects to https.

5. Core Web Vitals and performance

Google's documentation defines three Core Web Vitals and the thresholds for a good experience, measured at the 75th percentile of page loads.

INP replaced First Input Delay as a Core Web Vital in March 2024, according to Google.

Checklist:

• Field data in Search Console's Core Web Vitals report and PageSpeed Insights shows good results for key page templates.
• Hero images are compressed, served in modern formats like WebP or AVIF, and sized correctly.
• The LCP image is not lazy-loaded and is prioritized.
• Fonts load without blocking text, using font-display settings.
• Third-party scripts like chat widgets and trackers are audited and deferred where possible.
• Images and embeds have defined dimensions to prevent layout shift.
• Heavy JavaScript is split, deferred, or removed.

Our guide to Core Web Vitals explained covers fixes for each metric.

6. Mobile

Google uses mobile-first indexing, meaning it primarily uses the mobile version of a page for indexing and ranking, as its Search Central documentation states.

• Mobile and desktop versions show the same main content, headings and structured data.
• Text is readable without zooming.
• Tap targets are large enough and spaced apart.
• No horizontal scrolling.
• Intrusive interstitials do not cover content on load.

7. JavaScript rendering

Many modern sites rely on JavaScript frameworks. Google can render JavaScript, but rendering can be delayed, and some other crawlers, including many AI crawlers, may not run JavaScript at all.

• Important content and links appear in the initial HTML, through server-side rendering or static generation, where possible.
• Links use standard anchor tags with href attributes.
• The URL Inspection tool in Search Console shows the rendered page with the expected content.
• Metadata like titles, descriptions and canonicals is present in the initial HTML.

8. Structured data

Structured data helps search engines understand your content and can make pages eligible for rich results.

• Organization markup on the homepage, with name, logo, URL and official profiles.
• Article markup on blog posts and guides.
• Breadcrumb markup where breadcrumbs exist.
• Product, Service, LocalBusiness or FAQ markup where relevant and accurate.
• Markup validated with Google's Rich Results Test and the Schema.org validator.
• Markup matches visible page content.

See our schema markup guide for examples.

9. On-page technical elements

• Every indexable page has a unique, descriptive title tag.
• Meta descriptions are unique and summarize the page.
• One clear H1 per page, with a logical heading hierarchy.
• Images have descriptive alt text.
• Language is declared in the HTML tag. Sites in several languages use hreflang correctly.

10. AI crawlers and AI search

AI search tools now send visitors and cite sources. Decide on purpose how your site treats them.

• robots.txt rules for AI crawlers are set deliberately. Major AI companies publish their crawler user agents, such as OpenAI's GPTBot and OAI-SearchBot, and Anthropic's ClaudeBot. Google-Extended controls use of content for Google's AI models separately from Search.
• Key content is available in server-rendered HTML.
• Company facts, such as what you do, where you operate and who you serve, are stated clearly and consistently across your site.
• Consider whether an llms.txt file makes sense for your site. It is a proposed convention, not a standard that search engines have committed to.

11. Security and hygiene

• HTTPS everywhere, with no mixed content warnings.
• No hacked content or spam pages. Check Search Console's security issues report.
• Staging and development sites are blocked from indexing with authentication, not only robots.txt.
• Old campaign pages and test pages are cleaned up.

Priority order when everything fails

If an audit turns up many issues, fix them in this order.

1. Anything blocking crawling or indexing of important pages.
2. Broken redirects, 404s and duplicate content on key pages.
3. Mobile and rendering problems that hide content.
4. Core Web Vitals failures on high-traffic templates.
5. Structured data and on-page refinements.

Getting a technical audit done

A technical audit is the foundation for every other SEO investment. If you want your site checked against this list with issues ranked by impact, book a business audit and we will deliver the findings and a fix plan in writing.