The 20-Point Technical SEO Baseline Every Site Should Pass

Technical SEO does not win rankings on its own. Relevant content and genuine links do that. What technical SEO does is make sure nothing gets in their way: that search engines can find every page, understand what it is, and show it well. This is the baseline we hold every page to, grouped into eight areas. Each point says what to check and why it matters.

Indexing and crawling

1. An XML sitemap that stays accurate

List every indexable URL in sitemap.xml, with a lastmod date that changes only when the page really changes. Search engines use the sitemap to discover pages and to decide what to recrawl. Google has said it uses lastmod when it is consistently accurate, and ignores priority and changefreq. A sitemap that still lists deleted pages, or misses new ones, wastes crawling on the wrong URLs.

2. A robots.txt with a safe default

robots.txt controls crawling, not indexing. Use it to keep crawlers out of admin areas and internal search results, and point it at your sitemap. Do not block CSS or JavaScript files, which search engines need to render the page. And remember that a page blocked in robots.txt can still be indexed from links; to keep a page out of results, use noindex instead.

3. Indexable by default, with an explicit noindex

Every public page should be indexable unless someone deliberately decides otherwise. The classic failure is a staging site's noindex that survives launch day. Make noindex a visible per-page toggle, not a hidden setting, and check for it after every migration.

4. A self-referencing canonical

Each page should declare its own absolute URL as canonical, without tracking parameters. This consolidates signals when the same page is reachable through several URLs, for example with ?utm_source= added. Override it only when the page genuinely duplicates another. Search engines treat canonicals as a strong hint rather than a command, so keep them consistent with your internal links and sitemap.

Titles and descriptions

5. A unique, well-sized title

The title is the clickable headline in search results. Keep it unique per page and roughly 50 to 60 characters, because longer titles get truncated. A title template, such as "{page} | Brand", keeps branding consistent without repeating it by hand. Search engines sometimes rewrite titles, usually when the original is vague, stuffed or duplicated.

6. A unique meta description

Descriptions are not a ranking factor, but they often become the snippet under your title, which affects whether people click. Write one per page, around 140 to 160 characters, that says what the page offers. Duplicate descriptions across many pages tell search engines nothing and are often replaced.

Content structure

7. One H1 per page

Google has said multiple H1s will not hurt rankings, so this point is about clarity rather than an algorithm. One H1 that states the page's topic gives readers, screen readers and search engines an unambiguous summary. It is also a useful discipline: if a page needs two H1s, it is probably two pages.

8. No skipped heading levels

Headings should form an outline: H2s under the H1, H3s under an H2. Screen reader users navigate by headings, and a jump from H2 to H4 breaks that outline. A logical structure also makes it easier for search engines to match sections of a page to specific queries.

9. Alt text on every meaningful image

Alt text describes an image for people who cannot see it, and helps search engines understand and rank images. Describe what the image shows in context. Purely decorative images should have an empty alt="" so assistive technology skips them, which is a deliberate choice, not a missing value.

Structured data

10. JSON-LD that matches the page

Structured data tells search engines explicitly what a page is. The core types for a marketing site are Organization and WebSite on every page, BreadcrumbList for hierarchy, Article for blog posts, FAQPage where a page answers questions, and SoftwareApplication with Offer on a pricing page for software. Not every type produces a rich result: Google limited FAQ rich results to well-known government and health sites in 2023. The markup still removes ambiguity, so it is worth having when it accurately reflects the visible content.

Links

11. Deliberate internal linking

Internal links are how crawlers discover pages and how authority flows through a site. Every important page should be reachable through normal links, not only the sitemap. Breadcrumbs and related-content links add structure, and descriptive anchor text tells search engines what the target page is about.

12. No broken links

A link to a 404 wastes crawling, drops the authority that link would have passed, and frustrates visitors. Check internal and outbound links on a schedule, and keep a log of 404s actually being requested, which shows broken links from other sites that you can fix with a redirect.

Images, performance and security

13. Modern, responsive images

Serve WebP or AVIF, which are typically much smaller than equivalent JPEGs, through srcset so phones do not download desktop-sized files. Set width and height so the browser reserves space and the layout does not jump. Lazy-load images below the fold, but never the main above-the-fold image, which should load as early as possible.

14. Core Web Vitals within target

Google's Core Web Vitals measure loading (Largest Contentful Paint under 2.5 seconds), responsiveness (Interaction to Next Paint under 200 milliseconds) and visual stability (Cumulative Layout Shift under 0.1), at the 75th percentile of real visits. Page experience is a ranking signal, though relevance outweighs it. Fast pages also convert better, which is reason enough.

15. Layouts that work on small screens

Google indexes the mobile version of your site. Check every template at 360 pixels wide: no horizontal scrolling, readable text without zooming, and tap targets large enough to hit with a thumb.

16. HTTPS everywhere, with HSTS

Every page should load over HTTPS, with HTTP requests redirected permanently, and an HSTS header telling browsers never to use plain HTTP for the site. HTTPS is a lightweight ranking signal, and browsers mark plain-HTTP pages as not secure, which hurts trust before a visitor reads a word.

URLs and redirects

17. Clean URLs, with a 301 whenever one changes

URLs should be short, lowercase, hyphenated and readable, such as /services/kitchen-design rather than /page?id=482. When a URL has to change, a permanent 301 redirect from the old address passes its signals to the new one. Point redirects straight at the final URL, because chains of redirects slow crawling and users alike.

Sharing and discovery

18. Open Graph and Twitter cards

These tags control how a page looks when shared on social networks and messaging apps: title, description and image. They are not a ranking factor, but a page shared with a proper 1200 by 630 image gets noticed and clicked. Set a default image for the site and override it on key pages.

19. Search Console verification

Verifying the site in Google Search Console gives you index coverage reports, sitemap submission, URL inspection and the search queries that bring people to each page. A verification meta tag is one way to prove ownership; a DNS record is another. Without it, you are diagnosing problems blind.

20. An llms.txt file

llms.txt is a proposed convention, introduced in 2024, for giving language-model tools a concise Markdown overview of a site and its key pages. It is not a standard, and no search engine has said it uses it for ranking. It costs little to provide, and a generated file you can edit is a reasonable hedge as AI assistants become another way people find businesses.

Putting the baseline to work

None of these points is difficult on its own. The hard part is keeping all twenty true on every page, after every edit, on every site you manage. That is why we built them into OdysseyCMS rather than leaving them to plugins: the editor enforces the structure points, publishing updates the sitemap and structured data, and the SEO health panel scores each page against all twenty with a direct link to each fix. See how the baseline works in the product, check what every plan includes, or read our guide to migrating a site without losing rankings, where most of these points get tested at once.