Technical SEO Audit Checklist: What to Check First

A technical SEO audit can turn up hundreds of “issues”, and most of them don’t matter. This is the order I work through on a new site, starting with the problems that can make whole sections of it invisible.

1. Can Google index the site at all?

Start with the problems that can stop everything:

• The search visibility setting. In WordPress, check Settings → Reading. “Discourage search engines” is often left on after launch.
• robots.txt isn’t blocking important sections, CSS or JavaScript.
• No stray noindex tags on templates that should be indexed. Check the page source, not just the SEO plugin.
• One version of the site, with http, www and non-www all redirecting to the same HTTPS address.

In Google Search Console, the page indexing report shows which pages Google has left out and why. It’s the single most useful place to start. If the site is indexed but still doesn’t rank, work through why a website doesn’t rank, and if traffic has suddenly dropped, start with why rankings drop.

2. Are the right pages indexed?

Compare what you want indexed with what Google has actually indexed. The usual gaps:

• Important pages marked “Crawled – currently not indexed”, which is often a sign of thin or duplicate content
• Thin pages that are indexed: tag archives, attachment pages, internal search results, filter URLs
• Canonical tags pointing to the wrong page, or Google choosing a different canonical from the one you set

3. The XML sitemap

• Lists only indexable, canonical URLs that return a 200 status
• Leaves out redirects, noindexed pages and 404s
• Is referenced in robots.txt and submitted in Search Console

4. Status codes and redirects

Crawl the site with a tool like Screaming Frog and look for:

• Internal links that point to 404s or redirects. Update them to point straight at the final URL
• Redirect chains and loops
• Soft 404s: “not found” pages that return a 200 status
• Old URLs from previous versions of the site that still have backlinks but now return a 404

5. Site architecture and internal links

• Every important page is reachable within a few clicks of the homepage
• Key service pages get links from relevant guides and related services
• There are no orphan pages with nothing linking to them
• Anchor text is descriptive, not “click here”

6. On-page basics, at scale

• Unique, descriptive title tags and meta descriptions
• One clear H1 per page, with a logical heading structure underneath
• No two pages chasing the same search intent (cannibalisation)
• Images with useful alt text and sensible file sizes

7. Speed and Core Web Vitals

Use real-user data first: the Core Web Vitals report in Search Console, or the field data in PageSpeed Insights. Lab tests help you diagnose, but they don’t show what your visitors actually experience. The usual fixes:

• Compress and correctly size images, and serve modern formats
• Don’t lazy-load the main image at the top of the page
• Cut unused CSS and JavaScript, which often comes from page builders and plugins
• Reserve space for images, embeds and ads to stop the layout jumping around

8. Mobile rendering

Google indexes the mobile version of your site. Check that content, internal links and structured data are the same on mobile as on desktop, and that nothing important is hidden behind elements that don’t render.

9. Structured data

• Business details match what the site actually shows
• Service, product, article and breadcrumb markup where it’s relevant
• Validated with Google’s Rich Results Test and the Schema Markup Validator
• No markup for content that isn’t visible on the page

10. Prioritise before you fix anything

A list of issues isn’t a plan. Rank each one by how many important pages it affects, how much it limits visibility, and how hard it is to fix. Indexing problems on revenue pages come first. Cosmetic warnings on low-value pages can wait, sometimes forever.