Technical SEO Audit Checklist: What Agencies Should Check First
A practical technical SEO audit checklist for agencies: crawling, indexing, site structure, speed, schema and how to prioritise fixes for clients.
A technical SEO audit finds what stops search engines from crawling, indexing and ranking a site. Most audit tools list hundreds of warnings. The skill is knowing which ones matter.
This checklist follows the order we use when we audit a site: start with what can block rankings completely, then move to what holds them back.
1. Crawling and indexing
If Google can’t crawl or index a page, nothing else matters. Check:
- robots.txt isn’t blocking important sections
- Key pages don’t carry a noindex tag by mistake
- The XML sitemap lists only pages you want indexed, and is submitted in Search Console
- Page indexing in Search Console: look at why pages are excluded, not just how many
2. Status codes and redirects
- Fix broken internal links (404s)
- Replace redirect chains with a single redirect
- Check that old URLs from past redesigns still redirect to the right page
- Make sure HTTP and www versions all redirect to one version of the site
3. Duplicate content and canonicals
- Every page should have a canonical tag pointing to the preferred URL
- Watch for duplicates created by parameters, filters and sorting, especially on ecommerce sites
- Check that paginated pages aren’t competing with the main category page
4. Site structure and internal links
- Important pages should be reachable within a few clicks from the homepage
- Find orphan pages with no internal links pointing to them
- Use descriptive anchor text in internal links
5. Speed and Core Web Vitals
- Review real-user data in Search Console, not just lab tests
- Check the main page templates, since one fix often covers hundreds of pages
- Common wins: compressed images, fewer render-blocking scripts and stable layouts
6. Structured data
- Validate schema markup with Google’s Rich Results Test
- Use the right types for the business: Organization, LocalBusiness, Product, FAQ, Article
- Fix errors and warnings reported in Search Console
How to prioritise the fixes
A good audit doesn’t stop at a list. For each issue, note:
- Impact: how much it affects rankings or traffic
- Effort: how long the fix will take
- Pages affected: one page, or a whole template
Fix high-impact, low-effort issues first. Present them in plain language, so your client understands why each fix matters.