A technical SEO audit checks whether search engines can crawl, render, index and understand your website. It is the part of SEO that content and links sit on: if Google cannot reach or process a page, nothing else about that page matters. This checklist explains what a proper technical SEO audit covers, which tools it uses, and how to tell the issues that affect rankings from the warnings that do not.
What is a technical SEO audit?
A technical SEO audit is a structured review of a website's infrastructure: how it is crawled, which URLs get indexed, how fast and stable its pages are, how it is structured and linked, and whether its code gives search engines clear signals. The output should be a prioritised list of fixes, not just a report of every warning a tool produced.
The tools a technical audit uses
- Google Search Console for indexing status, crawl stats, Core Web Vitals field data and manual actions.
- A site crawler such as Screaming Frog, Sitebulb or Semrush Site Audit, to see the site the way a bot does.
- PageSpeed Insights and Lighthouse for performance diagnostics.
- Server log files, on larger sites, to see what Googlebot actually requests.
- Google's Rich Results Test for structured data.
The technical SEO audit checklist
1. Crawlability
- Is
robots.txtblocking anything important, such as CSS, JavaScript or whole sections? - Does the XML sitemap exist, is it submitted in Search Console, and does it list only indexable, canonical URLs that return a 200 status?
- Are important pages reachable through normal links, rather than only through search boxes or JavaScript events?
- On large sites, is crawl budget wasted on filter combinations, session IDs or endless calendar pages?
2. Indexing
- What does the Page indexing report in Search Console show? "Crawled, currently not indexed" and "Discovered, currently not indexed" usually point to quality, duplication or internal linking problems.
- Are any important pages carrying a stray
noindextag, often left over from a staging site? - Do canonical tags point to the right URL, and does Google agree with your chosen canonical?
- Do HTTP and HTTPS, www and non-www, and trailing slash versions all redirect to one version?
3. Status codes and redirects
- Broken internal links returning 404s.
- Redirect chains (A to B to C) and loops, which waste crawl and slow users down.
- Internal links pointing at redirected URLs instead of the final address.
- Soft 404s: pages that say "not found" but return a 200 status.
- Server errors (5xx) in Search Console's crawl stats.
4. Core Web Vitals and speed
Google's Core Web Vitals are measured on real users. A page is considered "good" when, at the 75th percentile of visits:
| Metric | What it measures | Good threshold |
|---|---|---|
| Largest Contentful Paint (LCP) | Loading: when the main content appears | 2.5 seconds or less |
| Interaction to Next Paint (INP) | Responsiveness to clicks and taps | 200 milliseconds or less |
| Cumulative Layout Shift (CLS) | Visual stability as the page loads | 0.1 or less |
Common fixes include compressing and correctly sizing hero images, deferring non-essential JavaScript, reserving space for images and embeds, and improving server response time.
5. Site architecture and internal links
- Can important pages be reached within a few clicks of the homepage?
- Are there orphan pages with no internal links pointing to them?
- Does anchor text describe the page it links to?
- Are URLs short, readable and consistent?
6. Duplicate and thin content
- Near-identical pages, such as location pages with only the town name changed.
- Duplicate title tags and meta descriptions across many URLs.
- Parameter URLs and print versions creating copies of the same content.
7. JavaScript rendering
If content or links only appear after JavaScript runs, compare the raw HTML with the rendered page using the URL Inspection tool in Search Console. Where important content is missing from the initial HTML, server-side rendering or pre-rendering is usually the safest fix.
8. Structured data
- Is schema markup valid, with no errors in the Rich Results Test?
- Does it describe what is actually on the page? Markup that does not match visible content can be ignored or lead to a manual action.
- Are Organization, LocalBusiness, Product, Article and Breadcrumb types used where relevant?
9. Mobile and security
- Google indexes the mobile version of your site, so content and links must be present on mobile, not hidden behind desktop-only templates.
- The whole site should load on HTTPS with no mixed-content warnings.
10. International setup (if relevant)
Sites serving more than one country or language need correct hreflang annotations, with return links on every version. See our guide to hreflang tags.
How to prioritise what you find
Audit tools can produce hundreds of warnings. Rank each issue by two questions: how many important pages does it affect, and does it stop those pages being crawled, indexed or understood? A noindex on your main service page is urgent. A handful of images missing alt text on old blog posts is not. A good audit tells you which is which.
How often should you run a technical SEO audit?
Run a full audit before and after any redesign, platform change or migration, and at least once or twice a year otherwise. Between audits, a monthly crawl and a regular look at Search Console will catch most new problems early.
Frequently asked questions
What is included in a technical SEO audit?
Crawlability, indexing, status codes and redirects, Core Web Vitals and speed, site architecture and internal links, duplicate content, JavaScript rendering, structured data, mobile and HTTPS, and international setup where relevant.
How long does a technical SEO audit take?
A small business site can be audited in a few days. Large e-commerce sites with thousands of URLs, log files and complex templates take longer.
Can I do a technical SEO audit myself?
You can cover the basics with Search Console, PageSpeed Insights and a free crawler. The harder part is interpreting the results and knowing which fixes matter, which is where experience helps.
How much does a technical SEO audit cost?
Our SEO audits cost £900 to £2,500 depending on the size and complexity of the site. See our UK SEO pricing guide for more detail.
Need a hand?
Our technical SEO services are delivered by developers as well as SEOs, so we can fix what the audit finds. For a one-off review see SEO audit services, and if you are changing platform, read about SEO migration services.
