What is technical SEO?

Technical SEO is the part of search engine optimization that checks whether search engines can fetch and index the pages of a website. It removes what stops them. The work happens in the system behind the pages: in the database, the templates and the server. The wording of a page and the links from other sites belong to other parts of SEO.

What technical SEO covers

Crawling is the first field. A search engine sends a program, the crawler, that requests the pages of a site one after another. A page the crawler cannot fetch stays out of search. That happens when the robots.txt file blocks the page, or when the text appears only after a script runs.

Indexing is the second field. After the fetch, the search engine decides whether it stores the page in its index. Only a stored page can appear in the results. Search engines often fetch a page and then leave it out. A common reason: many pages come from one template and differ in a name only.

Duplicate addresses are the third field. In a shop, filters and sort orders create new addresses that show the same products again. The search engine then sees several versions of one page. The canonical tag in the code of the page names the original. When the tag points to the wrong address, the signals of the page are split.

Load time is the fourth field. Slow pages lose visitors. The cause is often a database query without an index, or a page that the server builds again on each request. Lighthouse measures the load time before and after a change.

What is crawl budget?

Crawl budget is the number of addresses a search engine fetches from one site in a given period. Google wrote its crawl budget guide for sites with more than a million pages that change weekly, and for sites with more than 10,000 pages that change daily (Google, crawl budget guide). A smaller site rarely runs out of crawl budget. It still loses pages to duplicates and wrong canonical tags.

Why a technical fault is a topic for management

A shop, a portal or a database with public pages builds its pages from records and templates. One template can produce thousands of pages, and a fault in it repeats on them. An SEO tool reports the symptom, such as duplicate titles or pages without an index entry. Marketing reads the report. The fix is a change in code or data, so it waits in the IT backlog until someone gives it priority.

A technical SEO audit lists these faults with their causes. A move to a new system or a new domain changes the addresses that search engines have stored. An SEO migration plans that move from an inventory of the old addresses and checks it after the launch.

Does technical SEO improve rankings?

Technical SEO promises no rankings. Positions depend on your competitors, your content and the search engine’s own changes. Technical SEO removes the faults that keep pages out of the index or split their signals. A second crawl after the release shows which faults are gone.

My work in technical SEO

I am an IT expert for data platforms. For more than twenty years I have built websites whose pages come out of a database. I programmed the websites and databases of a global real estate database on major construction projects. As editor in chief of an information portal on construction projects I reached more than one million readers a year by 2024. For an insurance group I built web portals and managed more than 100 top-level domains from 2016 to 2021.

I set up and run Linux servers. Redirect rules, response headers and caching are settings I can change myself. I measure load time with Lighthouse on my own machine. Claude and Codex write the changes to templates and queries under rules that a machine checks, and I review the result. As a technical SEO consultant I find the cause of a fault in the system and fix it at the source. I take on this work as a freelancer or as a permanent employee.