What a Technical SEO Audit Actually Checks

Why the order matters

The four areas below are sequential, and treating them as a checklist to work through in any order is the most common way an audit wastes money. There is no point optimising page speed on a page search engines cannot reach, and no point improving content on a page that is excluded from the index. Each layer depends on the one before it.

1. Crawlability — can search engines reach the pages?

The first question is whether a crawler can get to your content at all. Problems here are usually binary and usually severe: the page is either reachable or it is invisible.

• robots.txt directives that block more than intended — a disallow rule written for a staging environment and carried into production is a classic.
• Pages reachable only through JavaScript navigation, with no crawlable link.
• Orphan pages with no internal link pointing at them.
• Redirect chains and loops, which waste crawl budget and dilute signals.
• Server errors and timeouts under crawler load rather than under human load.

2. Indexation — are the right pages in the index?

Crawlable is not the same as indexed, and indexed is not the same as intended. Two failure modes exist and they pull in opposite directions.

The second is underrated. A site with thousands of near-duplicate indexed URLs is competing against itself and spreading crawl attention across pages nobody wants to find.

3. Site health — is the site good enough to rank?

This is where most published audits spend their time, partly because it is the easiest part to automate. It matters, but it matters less than the two layers above.

Rendering and mobile

Check what the page looks like to a crawler, not to you. Content that only appears after client-side rendering is at a disadvantage — with conventional search and considerably more so with AI answer engines, as covered in our AEO guide.

Speed, honestly assessed

Speed is a ranking factor and a conversion factor, and the second is usually the bigger commercial effect. The useful audit output is not a score but a short list of what is actually slow: oversized images, render-blocking scripts, and third-party tags are the usual culprits on business sites.

Broken links and stale references

Internal links to pages that no longer exist, and previously indexed URLs now returning 404 with no replacement. The second is worth particular attention after a site rebuild, when old URLs frequently disappear without anyone mapping them.

4. Structured signals — do they describe the site accurately?

• Canonical tags: present, self-referencing where they should be, and not pointing at the homepage across the site.
• XML sitemap: contains only real, indexable, canonical URLs — no redirects, no 404s, no parameter variants.
• Structured data: valid, and describing content that genuinely exists on the page.
• Titles and meta descriptions: unique per page, not templated to near-identity.
• Heading hierarchy: one H1 per page, levels not skipped.

How to tell a good audit from a tool export

1. 01It is prioritised by impact, not sorted by severity label. Fifty medium issues are not a plan.
2. 02Every finding has evidence — the URL, the header, the specific line — not just a category name.
3. 03It distinguishes defects from preferences. Missing canonicals are a defect; a heading you would have worded differently is not.
4. 04It states what was checked and what was not. An audit with no stated scope has no stated limits.
5. 05It leads with findings rather than a score out of 100.

Can you do this yourself?

Partly, and it is worth doing. Search Console will show you indexation and coverage problems for free, and it is the single most valuable source because it reports what Google actually did rather than what a third-party crawler simulated. Browser developer tools will show you rendering and speed problems on any page.

What is harder without experience is prioritisation — knowing which of thirty findings actually costs you traffic and which is noise. That judgement is most of the value, which is why the deliverable to insist on is a prioritised list with reasoning rather than a longer list.

Technical audit work sits inside our organic search service, and we place SEO and AEO specialists as managed remote roles where a business wants that capability ongoing rather than as a one-off engagement.