An SEO audit is a health check for your website's search visibility. Someone, or a tool, works through the site to find problems that keep pages out of Google or push them down the results, then turns those findings into a prioritised to-do list. A good audit tells you what to fix first, not just everything that could be better.
What an audit actually examines
Most audits cover four layers, roughly in this order of importance:
- Indexing and crawling. Are the pages you care about in Google? The Pages report in Google Search Console shows which URLs are indexed and why others are not.
- Technical health. Broken links, redirect chains, duplicate URLs, missing HTTPS, mobile problems and Core Web Vitals.
- On-page content. Titles, headings, thin or duplicated pages, and whether each page matches what searchers want.
- Links and reputation. Who links to the site, whether anything looks spammy, and for local firms, how listings and reviews look.
Crawling tools such as Screaming Frog, Ahrefs Site Audit or Semrush Site Audit fetch every page and flag issues automatically. The judgement comes afterwards: deciding which flags matter.
A small audit, start to finish
An accountancy firm with 25 pages notices enquiries from search have dropped. The audit finds three real problems: the new "Services" page carries a noindex tag copied from a template, four blog posts share the same title, and the contact page loads a large uncompressed photo that makes it slow on phones. A crawler also lists 140 "warnings" about things like missing H2s on legal pages, which can safely wait. Fixing the three real issues takes an afternoon.
How often to audit a small site
Run a light audit before and after any redesign, platform move or domain change, when organic traffic drops without explanation, and otherwise once or twice a year. A ten-page brochure site does not need a monthly 80-page report. For it, a quick Search Console review covers most of what matters.
Where audits go wrong
- Treating the tool score as the goal. A score of 100 from an audit tool does not mean pages will rank; it means the tool's checklist passed.
- Fixing in list order. An indexing block on your main service page outweighs fifty missing image alt attributes.
- Auditing without baseline data. Note current traffic, rankings and indexed page counts so you can tell whether fixes worked.
- Ignoring content quality. Automated tools are good at technical errors and poor at judging whether a page is genuinely helpful.
Related terms
- Technical SEO: the area most audit tools focus on.
- On-page SEO: the content side an audit should also review.
- Google Search Console: the free data source every audit should start from.
- Backlink: what a link profile review looks at.