Technical SEO: the 2026 checklist (indexation, speed, Core Web Vitals)
7 min
Technical SEO ensures that Google can crawl, index, and understand your site without obstacles. The 2026 priorities: clean indexation (robots.txt, sitemap), a fast and stable site (Core Web Vitals), perfect mobile compatibility (mobile-first indexing), and structured data in JSON-LD. These foundations determine the effectiveness of everything else in your SEO strategy.
Without a solid technical foundation, even the best content stays invisible. Here is the checklist of technical points to lock down in 2026.
Indexation and crawling
The first step is making sure Google finds and indexes your important pages — and only those pages.
- robots.txt file correctly configured, without accidental blocking.
- XML sitemap up to date, submitted via Google Search Console.
- Canonical tags to manage duplicate content.
- Handling of pages not to index (noindex on pages with no SEO value).
Speed and Core Web Vitals
Performance is a ranking factor and a key conversion driver. Google measures experience through Core Web Vitals.
- LCP (Largest Contentful Paint): aim for under 2.5 seconds.
- INP (Interaction to Next Paint): keep the interface responsive.
- CLS (Cumulative Layout Shift): avoid layout jumps.
- Optimize images, caching, code, and hosting to speed everything up.
Each additional second of load time significantly increases the bounce rate on mobile, reducing conversions.
Google Search Central
Mobile-first and structured data
Google prioritizes the mobile version of your site for indexing. It must offer the same content and quality as the desktop version.
Structured data (schema.org in JSON-LD) helps Google understand your content and unlocks rich results (reviews, FAQ, breadcrumb).
- Responsive display, with no text too small or elements too close together.
- schema Organization, LocalBusiness, FAQ, or Product markup as applicable.
- HTTPS active across the entire site.
FAQ
Are Core Web Vitals really decisive?
They are part of the page experience signals, but they do not replace content relevance. With equivalent content, a faster site will have an edge — and above all, speed improves conversion rates.
How do you check your site's indexation?
Google Search Console shows which pages are indexed and flags crawl errors. The site:yourdomain.com command in Google also provides a quick overview of known pages.