Digital marketing glossary

What is technical SEO?

Written and reviewed by L.K. Monu Borkala · Updated 10 November 2026

Definition

Technical SEO is the work of making a website easy for search engines to crawl, understand and index. It covers site structure, speed, mobile-friendliness, HTTPS, robots.txt, XML sitemaps, canonical tags, redirects, structured data and fixing errors. Good content can't rank if Google can't find or read it.

How it works

Search engines first crawl pages by following links and sitemaps, then render and index them. Technical SEO removes anything that blocks those steps. Typical checks include: is the page allowed in robots.txt and not marked noindex by mistake; is there one canonical URL for each piece of content; do old URLs 301-redirect to the right new ones; does the site load quickly and pass Core Web Vitals; does the mobile version contain the same content as desktop (Google uses mobile-first indexing); and is there an up-to-date sitemap submitted in Google Search Console. Search Console's Pages and Core Web Vitals reports show most of these problems for free.

Example

Picture an online saree store in Surat that relaunches its website. Traffic halves within a month. Search Console shows hundreds of old product URLs returning 404 errors and the new site accidentally blocking /products/ in robots.txt. The team fixes robots.txt, adds 301 redirects from every old URL to its new one and resubmits the sitemap. Over the next few weeks, the pages return to the index and traffic recovers.

An illustration: the business and the rupee figures are made up to show how the idea works.

Common mistake

Launching a redesigned website without redirecting old URLs, or leaving a 'noindex' tag from the staging site on the live site. Another mistake is chasing a perfect speed score while ignoring real problems such as pages that aren't indexed at all.