Technical SEO

What Is Technical SEO?

Technical SEO refers to the process of optimising the infrastructure of your website so that search engines can crawl, index and render it effectively. Unlike content SEO, technical SEO focuses on the backend β€” server configuration, site architecture, page speed, structured data and more.

You can have the best content in your industry, but if Google can’t crawl or index your pages, that content will never rank.

Why Technical SEO Matters

Technical SEO is the foundation. Content and links amplify a technically sound site. They do very little for a broken one. Technical issues like slow load times, broken internal links, duplicate content and crawl errors can suppress your rankings regardless of your content quality or link profile.

The Technical SEO Checklist

1. Crawlability

Google’s bots must be able to reach and crawl every important page on your site. Key checks:

  • robots.txt is not blocking important pages or resources
  • Internal links reach all important pages
  • No orphan pages (pages with no internal links pointing to them)
  • XML sitemap is present, up to date and submitted to Google Search Console
  • Crawl budget is being used efficiently (no wasted crawls on paginated, filtered or duplicate URLs)

2. Indexation

Crawlable doesn’t mean indexed. Check that:

  • Important pages are not set to noindex
  • Canonical tags are correctly implemented
  • Hreflang tags are correct for international sites
  • Google Search Console shows no indexation issues

3. Site Speed and Core Web Vitals

Page speed is a confirmed ranking factor. Google’s Core Web Vitals are the specific metrics Google uses:

  • LCP (Largest Contentful Paint): How long until the largest element loads. Target: under 2.5 seconds.
  • FID/INP (Interaction to Next Paint): How quickly the page responds to user interaction. Target: under 200ms.
  • CLS (Cumulative Layout Shift): How much the layout shifts during loading. Target: under 0.1.

Measure with PageSpeed Insights, Chrome UX Report and Search Console’s Core Web Vitals report.

4. HTTPS and Security

HTTPS is a confirmed ranking factor. All pages must be served over HTTPS with a valid certificate. Check for mixed content warnings and ensure HTTP redirects to HTTPS.

5. Duplicate Content

Duplicate content dilutes ranking signals. Causes include: www vs non-www, HTTP vs HTTPS, trailing slash vs non-trailing slash, paginated pages and URL parameters. Fix with canonical tags and consistent internal linking.

6. Structured Data (Schema Markup)

Schema markup helps Google understand your content and can unlock rich results (review stars, FAQs, product details). Implement:

  • Organization schema on your homepage
  • LocalBusiness schema for location pages
  • Service schema on service pages
  • Article schema on blog posts
  • FAQPage schema on pages with FAQs

7. Mobile Optimisation

Google uses mobile-first indexing β€” it primarily uses the mobile version of your site for ranking. Your site must be fully responsive, with the same content on mobile as desktop and no mobile-only interstitials.

How to Run a Technical SEO Audit

  1. Crawl your site with Screaming Frog or Sitebulb
  2. Check Google Search Console for errors, warnings and coverage issues
  3. Run PageSpeed Insights on your key pages
  4. Test structured data with Google’s Rich Results Test
  5. Review your Core Web Vitals in Search Console
  6. Check mobile usability in Search Console

What Are Core Web Vitals?

Core Web Vitals are a set of specific page experience metrics that Google uses as a ranking signal. Introduced in 2021, they measure real-world user experience β€” specifically loading performance, interactivity and visual stability.

The Three Core Web Vitals

LCP β€” Largest Contentful Paint

LCP measures how long it takes for the largest visible element (usually a hero image or headline) to load. It’s a proxy for perceived load speed β€” how quickly does the page feel ready?

Good: Under 2.5 seconds | Needs improvement: 2.5–4 seconds | Poor: Over 4 seconds

How to improve LCP:

  • Optimise and compress images (use WebP format)
  • Preload your LCP element using <link rel=”preload”>
  • Use a CDN to reduce server response time
  • Remove render-blocking resources
  • Use lazy loading for off-screen images only

INP β€” Interaction to Next Paint

INP (which replaced FID in 2024) measures overall responsiveness β€” how quickly does the page respond to all user interactions, not just the first one?

Good: Under 200ms | Needs improvement: 200–500ms | Poor: Over 500ms

How to improve INP:

  • Reduce JavaScript execution time
  • Break up long tasks (over 50ms)
  • Use web workers for heavy computations
  • Minimise third-party scripts

CLS β€” Cumulative Layout Shift

CLS measures visual stability β€” how much does the page layout shift unexpectedly during loading? Ads or images loading without reserved space cause high CLS.

Good: Under 0.1 | Needs improvement: 0.1–0.25 | Poor: Over 0.25

How to improve CLS:

  • Always specify width and height attributes on images and videos
  • Reserve space for ads with CSS
  • Avoid inserting content above existing content
  • Use transform animations instead of layout-triggering ones

How to Measure Core Web Vitals

  • Google Search Console β†’ Core Web Vitals report (real user data)
  • PageSpeed Insights β€” lab + field data per URL
  • Chrome DevTools Lighthouse β€” lab data for any page
  • CrUX Dashboard β€” historical trends

What Is Schema Markup?

Schema markup (also called structured data) is code you add to your HTML that helps search engines understand the content on your pages. It uses a standardised vocabulary from Schema.org that describes things like businesses, products, reviews, events and articles in a way machines can process.

Why Schema Markup Matters for SEO

Schema doesn’t directly boost rankings, but it can dramatically increase click-through rates by enabling rich results β€” enhanced search listings that show ratings, prices, FAQs and more directly in Google’s results. Higher CTR means more traffic for the same ranking position.

The Most Valuable Schema Types

LocalBusiness

Essential for any local business. Tells Google your name, address, phone, opening hours and geographic coordinates. Supports the Map Pack and local Knowledge Panel.

FAQPage

When implemented on a page with questions and answers, this can trigger FAQ rich results β€” expandable Q&A directly in the SERP. Can significantly increase your organic real estate.

Review / AggregateRating

Enables review stars in search results for products, services and local businesses. One of the highest-impact rich results for click-through rate.

Article / BlogPosting

Marks up blog posts and news articles. Can enable Top Stories eligibility and article rich results.

Service

Describes a specific service offered by your business β€” useful for service pages that don’t have reviews yet.

How to Implement Schema Markup

The recommended format is JSON-LD (JavaScript Object Notation for Linked Data), placed in a script tag in your page’s <head> or <body>. It’s easy to add without changing your HTML.

How to Test Schema Markup

  • Google Rich Results Test β€” tests eligibility for rich results
  • Schema.org Validator β€” validates against Schema.org spec
  • Google Search Console β†’ Enhancements β€” reports on implemented structured data