Technical SEO Audit Guide: Find Every Issue in 6 Steps
You can get a free starting point with SitemapFixer's free SEO audit, which checks your sitemap coverage, canonical setup, and indexing signals automatically.
Step 1: Check crawlability
Start with robots.txt at yoursite.com/robots.txt. Verify it is not blocking important pages. Check Google Search Console under Settings then Crawl Stats to see how many pages Googlebot crawled and what response codes it received. A high percentage of 4xx or 5xx responses indicates crawl errors requiring investigation. Use the URL Inspection tool on your most important pages to confirm Googlebot can access them.
Step 2: Audit indexing
In Google Search Console, go to Indexing then Pages. Review each non-indexed category: Crawled not indexed (content quality issue), Duplicate without canonical (canonicalization problem), Blocked by robots.txt (crawl blocking), and noindex tag (intentional or accidental exclusion). Compare the number of indexed pages to your total published pages. A significant gap indicates indexing problems.
Step 3: Fix redirect chains and broken links
Use Screaming Frog or a similar crawler to crawl your site and identify: 404 pages, redirect chains (A redirects to B which redirects to C - consolidate to direct), redirect loops, and pages with too many redirects. Export all 3xx and 4xx response codes and fix them systematically. Every broken link wastes crawl budget and every redirect chain loses a small amount of PageRank.
Step 4: Check canonical tags
Export all canonical tags from your crawl and verify: every page has a canonical tag, all canonicals are self-referencing or point to the correct canonical URL, no pages have canonicals pointing to different domains (common after migrations), and paginated pages use self-referencing canonicals rather than pointing to page 1.
Step 5: Validate structured data
Use Google Rich Results Test on your key page templates to verify schema markup is valid. Check Google Search Console under Enhancements for any structured data errors. Fix invalid schema before worrying about adding new schema types. Common issues: missing required properties, incorrect types, and URL format mismatches.
Step 6: Measure Core Web Vitals
Check Google Search Console Core Web Vitals report for field data on your actual pages. Run PageSpeed Insights on your homepage, a key blog post, and a product or landing page. Identify the LCP element and whether it is being preloaded, check for CLS by using Chrome DevTools Layout Shift Regions, and look for INP issues using the Performance panel with interactions recorded.
Step 7: Audit internal linking
Export your site crawl and filter for pages with fewer than 2-3 internal links pointing to them — these are your orphan or near-orphan pages. Cross-reference against your most important pages: any page that ranks well or has strong content should have multiple internal links from relevant pages. Check that your navigation links to your most valuable pages, that blog posts link to related posts, and that every new page you publish has inlinks added from existing content within the first 48 hours of going live.
Step 8: Check mobile rendering
Google indexes the mobile version of your pages. Use Chrome DevTools device simulation to view your key pages on mobile. Check for: text that is too small to read without zooming, buttons and tap targets smaller than 48px, content wider than the viewport, interstitials that block the full page on mobile, and horizontal scrolling. Also use Google Search Console's Mobile Usability report under Experience to see pages Google has flagged as having mobile issues.
Step 9: Review your sitemap for quality
Open your sitemap.xml and audit it critically. Verify: every URL returns a 200 status (no redirects or errors), every URL has a canonical tag pointing to itself (no non-canonical URLs in the sitemap), no URLs have noindex tags, and lastmod dates are accurate and updated when content changes. Remove any URLs for deleted pages, tag archives with thin content, paginated pages beyond page 1, or any page you would not want to rank in Google. A leaner, curated sitemap performs better than a comprehensive one.
Step 10: Document findings and prioritize fixes
A technical SEO audit is only valuable if it leads to action. Export your crawl data, Search Console issues, and Core Web Vitals findings into a single spreadsheet. Categorize each issue by severity: Critical (directly blocking indexing or causing ranking loss), High (significant impact, fix within 2 weeks), Medium (meaningful but not urgent), and Low (minor improvements). Share the report with your development team with clear reproduction steps and expected impact. Schedule a re-audit in 30-60 days to verify fixes were implemented correctly and check for regressions.