How to Do a Technical SEO Audit Step by Step

Technical SEO refers to the infrastructure of your website — how it is built, how fast it loads, how easy it is for search engines to crawl and understand. Technical problems can prevent even excellent content from ranking well, so auditing this layer of your site is an essential starting point for any serious SEO effort.

This guide walks through the key areas of a technical SEO audit in a logical order, from checking that Google can access your site at all, through to fine-grained performance metrics and structured data. You do not need to fix every issue found — prioritise those that affect the most pages or have the clearest impact on crawling and ranking.

Step one: check crawlability and indexation

The first question in any technical audit is whether Google can actually access your pages. Start with Google Search Console — if you have not already set it up, do that before anything else. In the Coverage or Indexing report, you will see which pages are indexed, which are excluded, and why. Common exclusion reasons include noindex tags, pages blocked by robots.txt, and pages with canonical tags pointing elsewhere.

Download a crawl of your site using a tool like Screaming Frog (free for up to five hundred URLs) or Sitebulb. This mimics how a search engine spider moves through your site and surfaces broken internal links, redirect chains, pages returning error codes, and pages that exist but are not linked to from anywhere else on your site (orphan pages).

Check your robots.txt file directly at yourwebsite.co.uk/robots.txt. Ensure you are not accidentally blocking important sections of your site. Check your XML sitemap is present, submitted in Search Console, and contains only canonical, indexable URLs. A sitemap that includes redirected or noindexed URLs wastes crawl budget and can confuse Google.

Step two: assess site speed and Core Web Vitals

Google’s Core Web Vitals are a set of real-world user experience metrics that influence rankings. The three core metrics are Largest Contentful Paint (LCP), which measures how long the main content takes to load; Cumulative Layout Shift (CLS), which measures how much the page visually shifts as it loads; and Interaction to Next Paint (INP), which measures how quickly the page responds to user input.

Run your key pages through Google PageSpeed Insights, which shows your Core Web Vitals scores and provides specific recommendations for improvement. In Google Search Console, the Core Web Vitals report shows your performance across all pages at scale, segmented by mobile and desktop. Pages scoring "Poor" should be prioritised for improvement.

Common fixes for slow LCP include optimising or compressing the hero image, using a content delivery network to serve static assets from locations close to your visitors, and deferring non-critical JavaScript. CLS is often caused by images or ads without explicit dimensions that shift the page layout as they load; specifying width and height attributes on images is the simplest fix.

Step three: check HTTPS, canonicals, and structured data

Confirm your entire site is served over HTTPS and that there are no mixed-content warnings. Use a tool like Why No Padlock to scan for elements loading over HTTP on HTTPS pages. Ensure all HTTP versions of your URLs redirect permanently (301) to their HTTPS equivalents, and that www and non-www versions redirect to a single canonical version.

Review canonical tags across key page types. Canonical tags tell Google which version of a URL is the definitive one when multiple URLs show similar content. Misconfigured canonicals — pointing to the wrong page, or missing from paginated or filter pages — are a common cause of indexation problems on larger sites.

Finally, check your structured data implementation using Google’s Rich Results Test tool. Structured data helps Google understand your content and can unlock rich result features — star ratings, FAQ accordions, breadcrumbs, event details — in search listings. Validate that your markup is error-free and covers the content types most relevant to your business.