Technical SEO Audit: Complete Checklist Guide 2026
Run a comprehensive technical SEO audit with this 2026 checklist. Crawlability, indexation, site speed, mobile usability, and structured data checks.
Technical SEO signals Google evaluates
Avg. crawl budget wasted on large sites
Higher CTR for pages passing Core Web Vitals
Of top sites use any schema markup
Key Takeaways
Technical SEO is the foundation every other optimization strategy rests on. You can produce brilliant content and earn hundreds of backlinks — but if Googlebot cannot crawl your pages, if your LCP is 8 seconds, or if your canonical tags are broken, those investments return nothing. A systematic technical audit is how you find and fix the infrastructure problems silently suppressing your rankings.
This guide covers all eight audit dimensions in execution order — the sequence matters because crawlability issues must be resolved before indexation analysis, and indexation must be clean before structured data validation makes sense. Work through each section methodically and document every finding in a prioritized issue log.
1. Crawl Analysis
Crawl analysis reveals how search engine bots navigate your site — which pages they find, which they skip, and how efficiently they use their crawl budget. Crawl budget is a finite resource: Googlebot allocates a crawl rate limit per domain based on your server capacity and an overall crawl demand score based on page importance.
Robots.txt Review
Your robots.txt is the first document Googlebot reads. Errors here block crawling globally or for entire directories. Validate at yourdomain.com/robots.txt and in Google Search Console's robots.txt tester.
| Check | What to Look For | Pass Criteria |
|---|---|---|
| File accessible | Returns 200 status code | 200 OK, not 404 or 500 |
| No accidental blocks | Disallow: / blocks all crawling | No wildcard disallow for Googlebot |
| Sitemap declared | Sitemap: directive present | Absolute URL to sitemap index |
| Faceted URLs blocked | Parameter-generated URLs | Disallowed or managed via GSC URL params |
| Admin/login blocked | /admin/, /wp-admin/, /login/ | Disallowed (not indexed) |
Crawl Budget Optimization
2. Indexation Review
Indexation review ensures Google is indexing the pages you want ranked and excluding the pages you do not. Use the site:yourdomain.com operator in Google Search to get a rough index count, then cross-reference with Google Search Console's Pages report for detailed status breakdowns.
GSC Pages Report Audit
The Pages report in GSC categorizes every URL Google has encountered into indexed and not-indexed states. Each non-indexed status has a specific cause:
| GSC Status | Meaning | Action Required |
|---|---|---|
| Crawled - currently not indexed | Google crawled but chose not to index | Improve content quality, add internal links |
| Discovered - currently not indexed | Found via sitemap but not yet crawled | Submit URL inspection, improve crawl rate |
| Duplicate without canonical | Near-identical page without canonical tag | Add self-referencing canonical tags |
| Page with redirect | URL redirects to another destination | Verify redirect destination is correct |
| Blocked by noindex | Noindex tag present — intended exclusion | Verify intentional; remove if accidental |
| Not found (404) | URL returns 404 status code | Fix broken URLs or implement 301 redirects |
Canonical Tag Audit
Canonical tags tell Google which version of a page to treat as authoritative when multiple URLs serve identical or near-identical content. Canonicalization errors are among the most common — and most impactful — technical SEO failures.
3. Site Speed Audit
Page speed is a confirmed Google ranking factor — and more importantly, it directly affects user behavior. Google's Core Web Vitals (CWV) are the primary performance metrics used in ranking assessments. Measure CWV using field data (real user measurements from Chrome UX Report) rather than lab data (simulated tests) for accurate ranking signal evaluation.
Core Web Vitals Thresholds
| Metric | Good | Needs Improvement | Poor | What It Measures |
|---|---|---|---|---|
| LCP | ≤ 2.5s | 2.5s–4.0s | > 4.0s | Largest content element load time |
| INP | ≤ 200ms | 200ms–500ms | > 500ms | Interaction-to-next-paint responsiveness |
| CLS | ≤ 0.1 | 0.1–0.25 | > 0.25 | Visual stability during page load |
LCP Optimization Checklist
LCP is the most impactful CWV metric for most websites. The LCP element is typically a hero image, H1 text block, or above-the-fold video thumbnail.
4. Mobile Usability
Google uses mobile-first indexing for all sites — meaning the mobile version of your site is what Google evaluates for ranking purposes. Even if 60% of your traffic is desktop, Google's ranking signal comes from mobile crawls. Mobile usability issues reported in GSC directly correlate with ranking suppression on mobile searches, which now account for approximately 59% of all Google searches globally.
| Issue | Impact | Fix |
|---|---|---|
| Text too small to read | GSC mobile usability error | Minimum 16px base font size |
| Clickable elements too close | High bounce rate on mobile | Minimum 48x48px touch targets with 8px spacing |
| Content wider than screen | Horizontal scroll; poor UX | Add viewport meta tag; use relative widths |
| Interstitials blocking content | Google penalty for intrusive interstitials | Use banners instead of full-screen overlays |
| Viewport not configured | Desktop layout on mobile devices | Add <meta name="viewport" content="width=device-width"> |
Test mobile usability using Google's Mobile-Friendly Test tool (search.google.com/test/mobile-friendly), GSC's Mobile Usability report, and real device testing on 360px-390px viewport widths. Do not rely solely on browser DevTools responsive mode — it does not replicate real device touch interaction or font rendering.
5. Structured Data Validation
Structured data (schema markup) communicates explicit page meaning to Google — enabling rich results like star ratings, article dates, how-to steps, product prices, and sitelinks. Rich results increase organic CTR by 20–30% on average. However, incorrect implementation generates Manual Actions or rich result eligibility revocation.
Include datePublished, dateModified, author
Requires name, offers (price, availability)
Steps with text required; images recommended
itemListElement array; position required
address, telephone, openingHours required
startDate, location, name required
Validate all structured data using Google's Rich Results Test (search.google.com/test/rich-results) and Schema.org Validator. Check GSC's Enhancements section for implementation errors reported from your live site. Common errors include missing required properties, incorrect data types (string vs. number), and conflicts between JSON-LD and Open Graph metadata.
6. Internal Linking
Internal links serve three functions in technical SEO: they enable crawl discovery (Googlebot follows links to find new pages), distribute PageRank authority through the site architecture, and establish topical relevance relationships between pages. A systematic internal linking audit typically surfaces 40–60% of pages with zero inbound internal links — orphan pages that cannot be discovered, ranked, or contribute to topical authority.
Internal Linking Audit Checklist
For new content, the most impactful internal linking practice is adding contextual links from your highest-authority existing pages to newly published content within 24 hours of publication. This accelerates Googlebot discovery and initial PageRank flow to the new page.
See our guide on web development best practices for site architecture decisions that affect internal linking structures — flat site architectures (3 levels max) distribute link equity more efficiently than deeply nested category hierarchies.
7. Security (HTTPS)
HTTPS has been a confirmed Google ranking signal since 2014. Beyond ranking, security issues cause Chrome to display interstitial warnings that suppress click-through rates by up to 45% and destroy user trust. A complete security audit covers certificate validity, mixed content, redirect configuration, and HSTS implementation.
| Security Check | Tool | Pass Criteria |
|---|---|---|
| SSL certificate valid | SSL Labs / browser padlock | Valid, not expired, grade A or A+ |
| Mixed content absent | Chrome DevTools Console | Zero mixed content warnings |
| HTTP redirects to HTTPS | curl -I http://yourdomain.com | 301 redirect to HTTPS version |
| HSTS header present | Response headers check | max-age minimum 31536000 seconds |
| No www/non-www duplication | Manual test both versions | One canonical version with 301 redirect |
| Security headers | securityheaders.com | X-Content-Type-Options, CSP, Referrer-Policy |
Mixed Content Resolution
Mixed content occurs when an HTTPS page loads HTTP resources (images, scripts, stylesheets). Chrome blocks mixed active content (scripts, iframes) and warns on mixed passive content (images). Run Chrome DevTools' Network tab filtered to "HTTP" on your pages to identify all mixed content sources. Common culprits: hardcoded HTTP image URLs in CMS content, third-party embed codes, and legacy font or icon CDN links.
8. Monitoring Setup
A technical SEO audit is a point-in-time snapshot. Without ongoing monitoring, new deployments, CMS updates, and third-party script changes silently introduce regressions. Sites without monitoring see an average 12% organic traffic decline per quarter from accumulating unfixed issues. Set up layered monitoring across four domains: uptime, crawl health, CWV, and GSC alerts.
- UptimeRobot or Pingdom for 1-minute interval checks
- Alert on 5xx errors, SSL expiry (30 days in advance), and slow response times (>3s TTFB)
- Configure status page for client-facing transparency
- Weekly Screaming Frog crawl on staging before deployments
- Monthly full site crawl to detect new orphan pages, broken links, or redirect changes
- GSC Coverage report review every 2 weeks
- GSC Core Web Vitals report for field data (real users)
- CrUX Dashboard in Looker Studio for trend tracking
- PageSpeed Insights API for automated regression tests in CI/CD pipeline
- Enable email alerts in GSC for manual actions, security issues, and indexing errors
- Monitor Search Analytics for sudden CTR or impression drops (>20% week-over-week)
- Track position changes for your top 50 keyword targets monthly
Executing Your Technical SEO Audit
Work through this checklist in order. Crawl analysis must precede indexation review. Indexation must be clean before structured data validation is meaningful. Build a prioritized issue log as you go, categorizing findings by P0–P3 severity. Share the log with your development team and set resolution deadlines. A technical SEO audit without implementation follow-through produces no ranking improvement.
The sites consistently winning organic search in competitive niches are those with clean technical foundations maintained through ongoing monitoring — not those that ran one audit three years ago. Technical SEO is infrastructure maintenance, not a one-time project.
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Frequently Asked Questions
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