SEO guide · updated 30 September 2026

Technical SEO: crawling, indexing, speed and mobile

Technical SEO makes sure search engines can crawl, render and index your website, and that it loads fast and works well on phones. If the technical foundation is broken, great content can't rank.

Technical SEO checklist

  1. Crawlability: important pages are linked internally and not blocked in robots.txt.
  2. Indexability: no accidental noindex tags; canonical tags point to the right URLs.
  3. XML sitemap: lists every page you want indexed, submitted in Google Search Console.
  4. One version of the site: http, www and trailing-slash variants all redirect to one canonical address.
  5. HTTPS with a valid SSL certificate.
  6. Mobile-friendly design: Google uses mobile-first indexing.
  7. Core Web Vitals: LCP under 2.5s, INP under 200ms, CLS under 0.1.
  8. Clean redirects: no chains or loops; broken links fixed.
  9. Structured data valid in Google's Rich Results Test.
  10. Site architecture: important pages within a few clicks of the homepage; logical URL folders.
  11. Hreflang for multi-language or multi-country sites.
  12. JavaScript rendering: key content and links are in the HTML or render reliably.

Crawling and indexing

Crawling is Googlebot discovering pages by following links and sitemaps. Indexing is Google storing and understanding them. Use the Pages report in Google Search Console to see which pages are indexed and why others aren't (for example "Crawled, currently not indexed", which usually means Google didn't see enough value in the page).

robots.txt tells crawlers which areas not to crawl. It doesn't remove pages from Google; use a noindex tag for that.

Site speed and Core Web Vitals

Core Web Vitals are Google's page experience metrics: Largest Contentful Paint (loading), Interaction to Next Paint (responsiveness) and Cumulative Layout Shift (visual stability). Improve them by compressing images, using caching and a CDN, reducing heavy scripts and choosing fast hosting. South African sites often gain by hosting locally or using a CDN with local edge servers.

Mobile SEO

Most South African searches happen on phones, and Google indexes the mobile version of your site. Use a responsive design, readable text without zooming, tap targets that are easy to hit and no intrusive pop-ups.

JavaScript SEO

Sites built with React, Angular or Vue can rank, but Google must render the JavaScript first. Server-side rendering or static generation (for example with Next.js) is safest. Make sure links are real <a href> links and that important content doesn't depend on clicks to load.

Questions answered

What is technical SEO?

Technical SEO is optimising a website's infrastructure (crawling, indexing, speed, mobile usability, HTTPS, structured data and site architecture) so search engines can access and rank it.

What is crawling in SEO?

Crawling is when search engine bots discover and read web pages by following links and sitemaps.

What is indexing in SEO?

Indexing is when a search engine stores a crawled page in its database so it can appear in search results.

What is an XML sitemap?

An XML sitemap is a file listing the URLs you want search engines to index. Submit it in Google Search Console.

What is robots.txt?

robots.txt is a text file at the root of your site that tells crawlers which paths they may or may not crawl.

Does site speed affect SEO?

Yes. Page experience, including Core Web Vitals, is part of Google's ranking systems, and slow sites lose visitors before they convert.

What are Core Web Vitals?

Core Web Vitals are Google's metrics for loading (LCP), responsiveness (INP) and visual stability (CLS).

What is mobile-first indexing?

Mobile-first indexing means Google uses the mobile version of your pages for indexing and ranking.

Does HTTPS affect SEO?

Yes, HTTPS is a lightweight ranking signal and browsers warn users about non-secure sites.

What is crawl budget?

Crawl budget is how many pages Google is willing and able to crawl on your site in a given time. It mainly matters for very large sites.

What is hreflang?

Hreflang is a tag that tells Google which language or country version of a page to show different users.

Is JavaScript bad for SEO?

Not necessarily, but content that only appears after JavaScript runs can be indexed slowly or incompletely. Server-side rendering is safest.

Does hosting affect SEO?

Indirectly: slow or unreliable hosting hurts speed and uptime, which affect rankings and users.

What is a technical SEO audit?

A technical SEO audit checks crawling, indexing, speed, mobile usability, redirects, structured data and site structure, and lists fixes by priority. See our Technical SEO Cleanup service.

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