A technical SEO audit is a systematic review of your website’s technical health — the foundational elements that determine whether Google can effectively crawl, index, and rank your pages. Unlike content or link building, technical SEO issues are often invisible to the naked eye.
They sit beneath the surface, silently limiting your rankings regardless of how good your content is. Running a thorough technical SEO audit uncovers these hidden issues and prioritises the fixes that produce the largest ranking improvements. This step-by-step guide walks through every component of a complete technical audit.
What You Need Before Starting
Before running a technical SEO audit, gather the tools and access required to complete each section. You need:
- Google Search Console — free, provides Google’s own data on your site’s indexing, crawl errors, and performance
- Google Analytics 4 — for traffic and engagement data
- Screaming Frog SEO Spider — crawls your site and collects technical data on every URL (free up to 500 URLs, paid for larger sites)
- PageSpeed Insights — tests page speed and Core Web Vitals (free)
- Ahrefs or Semrush — for backlink analysis and keyword data (paid, but free trials available)
With these tools in place, work through the audit in the order presented here — from foundational indexing issues outward to performance and off-page signals.
Step 1: Check Indexing Status and Coverage
Your first question is whether Google can see your site and what it’s actually indexing. In Google Search Console, navigate to the Indexing > Pages report.
Review the following:
- Total indexed pages — does this number match your expected page count? A significantly lower number indicates indexing problems worth investigating
- Reasons for exclusion — review each exclusion category: Noindex, Crawled but not indexed, Discovered but not indexed, Duplicate without canonical, Soft 404, 404
- Not indexed pages — identify important pages that should be indexed but aren’t
For each exclusion category, export the affected URLs and prioritise fixes. Pages with “Crawled but not indexed” status need content quality review — Google has visited the page but chosen not to index it, usually because the content is thin or too similar to other indexed pages. Pages with “Discovered but not indexed” may have crawl budget issues or internal linking gaps.
Use the URL Inspection tool to check your most important individual pages. Verify each is indexed, mobile-friendly, and has no specific issues flagged.
Step 2: Review Your Robots.txt File
Your robots.txt file tells Googlebot which pages it can and cannot crawl. Misconfigurations here can unintentionally block Google from your entire site or from critical page categories.
Access your robots.txt at yourdomain.com/robots.txt. Review every Disallow rule and confirm each is intentional.
Common mistakes to look for:
- Disallow: / — this blocks Google from crawling your entire site. This setting is common in WordPress development mode and is often accidentally left active after launch
- Blocking CSS or JavaScript files — if Googlebot can’t access your stylesheets and scripts, it can’t render your pages correctly and may misunderstand their content
- Blocking URL patterns that include important pages
- Missing or overly broad allow rules that conflict with disallow directives
Test your robots.txt in Google Search Console’s robots.txt tester tool — it simulates Googlebot’s interpretation of your rules and flags any pages being accidentally blocked.
Step 3: Analyse Your XML Sitemap
Your XML sitemap is the roadmap you provide to Google for indexing your content. A poorly maintained sitemap slows indexing and wastes crawl resources.
In Google Search Console under Indexing > Sitemaps, verify your sitemap is submitted and has been successfully read by Google. Check the number of submitted URLs versus indexed URLs — a significant discrepancy indicates pages in your sitemap that Google isn’t indexing.
Review the sitemap itself for the following issues:
- Non-200 status pages — URLs returning redirects, 4xx, or 5xx status codes should be removed from the sitemap
- Noindexed pages — pages with noindex tags should not be included in the sitemap
- Missing pages — important pages that should be indexed but aren’t in the sitemap
- Outdated lastmod dates — if your sitemap generator never updates modification timestamps, Google may deprioritise recrawling updated content
Regenerate your sitemap using your SEO plugin — Rank Math or Yoast — after making corrections. Resubmit in Google Search Console and monitor the submitted vs indexed ratio over the following weeks.
Step 4: Audit Your Site Architecture and Internal Linking
Site architecture determines how authority flows through your site and how easily Googlebot can discover all your pages. Run Screaming Frog and review the internal linking data.
Check the following:
- Click depth — how many clicks from the homepage does it take to reach important pages? Pages more than 3 clicks deep receive less crawl priority and less internal link equity
- Orphan pages — export all URLs from Screaming Frog and compare against your sitemap. Pages in the sitemap but not found by the crawler have no internal links pointing to them
- Internal link count per page — identify important pages receiving very few internal links and add links from relevant content
- Broken internal links — Screaming Frog’s Response Codes tab flags all 4xx internal links. Fix these by updating the link to the correct current URL
Review your internal linking structure against your topic clusters. Pages within the same topical cluster should link to each other naturally. Pillar pages should receive links from every relevant cluster page. This architecture strengthens topical authority and distributes link equity to your highest-priority pages.
Step 5: Check for Duplicate Content Issues
Duplicate content confuses Google about which version of a page to index and rank, diluting your authority across multiple URLs. Use Screaming Frog to identify duplicate and near-duplicate pages.
Key duplicate content issues to fix:
- Missing canonical tags on pages with multiple accessible URL variations
- Canonical tags pointing to wrong URLs — self-referencing canonicals should point to the correct preferred URL
- HTTP vs HTTPS duplicates — if your site is accessible at both http:// and https://, verify that 301 redirects point all HTTP traffic to HTTPS and canonical tags consistently reference the HTTPS version
- WWW vs non-WWW duplicates — choose one version and redirect all traffic to it
- Trailing slash inconsistency — domain.com/page/ and domain.com/page are different URLs. Choose one format and redirect the other consistently
- Pagination duplicates — ensure paginated pages use proper rel=”next” and rel=”prev” or canonical tags pointing to the first page
A technical SEO audit is a comprehensive diagnostic health check that uncovers the hidden backend errors, broken links, and speed bottlenecks quiet stalling your rankings.
Step 6: Audit Page Speed and Core Web Vitals
Page speed is a confirmed ranking factor and a direct conversion factor. Run PageSpeed Insights on your homepage, top landing pages, and a sample of blog posts.
For each page, note:
- LCP score — should be under 2.5 seconds
- INP score — should be under 200 milliseconds
- CLS score — should be under 0.1
For pages failing these thresholds, note the specific issues flagged in the Opportunities and Diagnostics sections. The most common fixes are:
- Converting images to WebP format
- Compressing large images
- Enabling server-side caching
- Deferring non-critical JavaScript
- Specifying image dimensions to prevent layout shifts
- Eliminating render-blocking resources
Cross-reference with Google Search Console’s Core Web Vitals report to identify which of your actual URLs are failing at scale based on real user data. Fix the highest-traffic, lowest-performing pages first.
Full guidance on fixing each metric is covered in our dedicated Core Web Vitals guide.
Step 7: Review Your HTTPS and Security Status
Verify your site is fully served over HTTPS. Check that:
- Your SSL certificate is valid and not expired — browsers show a warning for expired certificates
- All pages redirect from HTTP to HTTPS via 301 redirects
- No mixed content exists — all resources (images, scripts, stylesheets) load over HTTPS
- Your canonical tags consistently reference HTTPS URLs
- Your sitemap references HTTPS URLs
Check your certificate expiry date and set a renewal reminder 30 days before expiry. Most managed hosting platforms renew Let’s Encrypt certificates automatically, but it’s worth verifying the auto-renewal is functioning.
Step 8: Check for Mobile-Friendliness Issues
Since Google uses mobile-first indexing, your mobile experience directly determines your rankings across all devices. Run Google’s Mobile-Friendly Test on your key pages.
Common mobile issues to look for:
- Text too small to read without zooming (below 16px body font size)
- Tap targets too small or too close together (below 48x48px)
- Content wider than the screen requiring horizontal scrolling
- Intrusive popups that cover the main content on mobile
- Mobile-specific 404 errors — pages accessible on desktop but not on mobile due to device-specific redirects
Review your mobile performance in Google Search Console’s Mobile Usability report under Experience. Fix all flagged issues starting with the highest-traffic pages.
Step 9: Audit Your Metadata Across Key Pages
Title tags and meta descriptions affect both rankings and click-through rates. Screaming Frog’s Page Titles and Meta Description tabs show your metadata across your entire site simultaneously.
Check for:
- Missing title tags — pages with no title tag
- Duplicate title tags — multiple pages sharing the same title
- Oversized title tags — titles over 60 characters that will be truncated in search results
- Missing meta descriptions — pages relying on Google’s auto-generated snippet
- Duplicate meta descriptions — same description used across multiple pages
- Oversized meta descriptions — descriptions over 160 characters that will be cut off
For all pages with issues, rewrite metadata according to the guidelines covered in our meta title and meta description guide. Prioritise your homepage, service pages, and top-ranking blog posts.
Step 10: Review Structured Data Implementation
Use Google’s Rich Results Test and Google Search Console’s Enhancements section to audit your structured data.
Check that:
- Key pages have appropriate schema markup implemented — LocalBusiness for your homepage, Article or BlogPosting for blog posts, FAQ for pages with question sections
- Schema markup contains no errors or warnings in the Rich Results Test
- Required properties for each schema type are present — missing required properties prevent rich result eligibility
- Schema doesn’t markup content not visible on the page
Add missing schema to high-priority pages and fix errors on existing implementation. This is particularly impactful for service businesses using LocalBusiness and FAQ schema, as covered in our guide to structured data in SEO.
Step 11: Analyse Your Backlink Profile
While backlinks are technically off-page, reviewing your link profile is a standard part of a comprehensive audit. Use Google Search Console’s Links report alongside Ahrefs or Semrush.
Assess:
- Total referring domains — is this growing over time?
- Domain authority distribution of linking sites
- Anchor text distribution — check for over-optimisation
- Toxic or spammy links requiring disavowal
- Lost backlinks — important links that previously pointed to your site but no longer do (broken target page, site restructure)
For lost links where your page moved to a new URL, implement 301 redirects from the old URL to recapture the lost link equity. For toxic links, add them to your disavowal file.
Step 12: Document Findings and Prioritise Fixes
The final step is producing a prioritised action list from your audit findings. Not all issues are equally urgent. Prioritise by impact and effort.
Critical — fix immediately:
- Noindex tag on important pages
- robots.txt blocking Googlebot from key pages
- HTTP site with no HTTPS redirect
- Core Web Vitals failures on highest-traffic pages
- Manual action in Google Search Console
High priority — fix within 2 weeks:
- Orphan pages with good content
- Duplicate content without canonical tags
- Broken internal links on important pages
- Missing metadata on key pages
- Oversized or poorly formatted images
Medium priority — fix within a month:
- Redirect chains that could be consolidated
- Missing schema markup on secondary pages
- Incomplete XML sitemap
- Low-priority crawl budget issues
Document every finding with the specific URL affected, the issue type, the recommended fix, and the priority level. This document becomes your technical SEO roadmap and a reference for tracking improvements over time.
Frequently Asked Questions (FAQs)
- How often should I run a technical SEO audit?
Run a full comprehensive audit quarterly for most sites. Run a lighter monthly check covering indexing status, Core Web Vitals, and crawl errors in Google Search Console. For large sites with frequent publishing or development activity, monthly full audits are warranted. Any significant site change — new CMS, redesign, migration — should trigger an immediate audit.
- Can I do a technical SEO audit without paid tools?
Yes, for most critical issues. Google Search Console, PageSpeed Insights, Google’s Mobile-Friendly Test, and Google’s Rich Results Test are all free and cover the most impactful technical issues. Screaming Frog’s free version handles sites up to 500 pages. For comprehensive backlink analysis, paid tools are necessary — but for on-site technical issues, free tools are sufficient for most small to medium sites.
- What is the most impactful technical SEO fix?
It depends on your site’s specific issues. However, across most sites audited, the highest-impact fixes are — in priority order — resolving indexing blocks, fixing Core Web Vitals on high-traffic pages, implementing canonical tags for duplicate content, and addressing orphan pages. Start with anything preventing Google from crawling or indexing your pages before addressing performance issues.
- How long does a technical SEO audit take?
For a small site (under 500 pages), a thorough audit takes 4 to 8 hours. For a medium site (500 to 5,000 pages), expect 1 to 3 days. For large sites (over 10,000 pages), a comprehensive audit is a week-long project. Implementation of fixes is separate and depends on the volume and complexity of issues found.
- Should I fix all technical issues or just the most critical ones?
Fix all issues you identify, but prioritise the most critical ones first. Leaving minor technical issues unresolved is less dangerous than leaving critical ones. After addressing critical and high-priority issues, work through medium and lower-priority fixes systematically. A technically clean site amplifies every other SEO investment — content, links, and local signals all perform better on a technically sound foundation.
- How quickly will rankings improve after fixing technical SEO issues?
Critical fixes — removing a noindex tag from an important page, fixing an HTTPS migration error — can produce ranking improvements within days as Google recrawls the corrected pages. Core Web Vitals improvements typically show ranking impact within 4 to 8 weeks. Structural improvements like canonical tag implementation and crawl budget optimisation take 6 to 12 weeks to fully reflect in Google’s index and rankings.
