freecourses.digital
Lesson progress: 0 of 3 activities done
All lessons in Technical SEO Auditing Lesson 3.1 of 84

Module 1: Introduction to Technical SEO Auditing

  1. 1.1What Is a Technical SEO Audit?
  2. 1.2Technical SEO Audit vs. General SEO Audit
  3. 1.3When Should You Audit a Website?
  4. 1.4Types of Technical SEO Issues
  5. 1.5Defining Audit Scope and Objectives

Module 2: Website Crawling and URL Discovery

  1. 2.1How SEO Crawlers Discover URLs
  2. 2.2Configuring a Website Crawl
  3. 2.3Crawl Scope, Limits, and Exclusions
  4. 2.4Internal Links and Crawl Depth
  5. 2.5Orphan Pages and URL Discovery
  6. 2.6Crawl Data vs. Search Engine Data
  7. 2.7Identifying Crawl Coverage Gaps

Module 3: HTTP Status Codes and Redirect Auditing

  1. 3.1Understanding HTTP Status Codes
  2. 3.2Finding 4xx Errors and Broken Links
  3. 3.3Identifying 5xx Server Errors
  4. 3.4Redirect Chains and Redirect Loops
  5. 3.5Internal Links to Redirected URLs
  6. 3.6301 vs. 302 Redirects
  7. 3.7Auditing 404 Pages and Soft 404s

Module 4: Crawlability and Indexability Auditing

  1. 4.1Crawling vs. Indexing
  2. 4.2Robots.txt Audit
  3. 4.3Meta Robots and X-Robots-Tag
  4. 4.4Noindex and Canonical Conflicts
  5. 4.5XML Sitemap Validation
  6. 4.6Canonical URL Auditing
  7. 4.7Identifying Indexability Conflicts
  8. 4.8Comparing Crawl Data with Google Search Console

Module 5: URL Structure and Duplicate Content Issues

  1. 5.1URL Structure and Normalization
  2. 5.2Duplicate URLs and Duplicate Pages
  3. 5.3HTTP vs. HTTPS and Hostname Variations
  4. 5.4Trailing Slashes and URL Parameters
  5. 5.5Pagination and Faceted Navigation
  6. 5.6Canonicalization Strategies
  7. 5.7Internal Linking to Preferred URLs

Module 6: Technical On-Page Auditing

  1. 6.1Missing and Duplicate Title Tags
  2. 6.2Missing and Duplicate Meta Descriptions
  3. 6.3Missing, Duplicate, and Multiple H1 Headings
  4. 6.4Heading Hierarchy and HTML Structure
  5. 6.5Missing Image Alt Attributes
  6. 6.6Internal Link and Anchor Text Issues
  7. 6.7Empty, Thin, and Near-Duplicate Pages
  8. 6.8Auditing HTML Metadata at Scale

Module 7: Website Performance and Core Web Vitals

  1. 7.1Core Web Vitals: LCP, INP, and CLS
  2. 7.2Lab Data vs. Field Data
  3. 7.3Identifying Slow Pages
  4. 7.4Image and Resource Optimization Opportunities
  5. 7.5JavaScript and CSS Performance
  6. 7.6Mobile Usability and Responsive Rendering
  7. 7.7Prioritizing Performance Fixes

Module 8: JavaScript SEO and Rendering

  1. 8.1How Search Engines Process JavaScript
  2. 8.2HTML Source vs. Rendered HTML
  3. 8.3Client-Side vs. Server-Side Rendering
  4. 8.4JavaScript-Generated Content and Links
  5. 8.5Rendering Failures and Missing Content
  6. 8.6Lazy Loading and Crawl Accessibility
  7. 8.7Diagnosing JavaScript SEO Problems

Module 9: Structured Data and Schema Auditing

  1. 9.1Structured Data and Schema.org Basics
  2. 9.2JSON-LD and Structured Data Formats
  3. 9.3Finding Structured Data Across a Website
  4. 9.4Detecting Invalid or Incomplete Markup
  5. 9.5Schema Validation and Rich Result Eligibility
  6. 9.6Conflicting or Duplicate Structured Data
  7. 9.7Prioritizing Schema Fixes

Module 10: Analyzing Audit Data and Prioritizing Issues

  1. 10.1Reading Crawl Reports and Exports
  2. 10.2Grouping URLs by Issue Type
  3. 10.3Identifying Root Causes vs. Symptoms
  4. 10.4Evaluating Severity, Impact, and Effort
  5. 10.5Separating Sitewide and Isolated Issues
  6. 10.6Identifying False Positives
  7. 10.7Building an Actionable Issue Register

Module 11: Technical SEO Audit Reporting

  1. 11.1Structuring a Technical SEO Audit Report
  2. 11.2Documenting Evidence and Affected URLs
  3. 11.3Writing Developer-Ready Recommendations
  4. 11.4Mapping Issues to Business and Search Impact
  5. 11.5Creating a Prioritized Remediation Roadmap
  6. 11.6Presenting Findings to Stakeholders
  7. 11.7Tracking Fixes and Ownership

Module 12: Fix Verification and Technical QA

  1. 12.1Re-Crawling After Fixes
  2. 12.2Comparing Before-and-After Crawl Results
  3. 12.3Verifying Redirects, Canonicals, and Indexability
  4. 12.4Detecting Regressions and Newly Introduced Issues
  5. 12.5Testing Website Changes Before Deployment
  6. 12.6Confirming Fixes with Search Console and Other Evidence
  7. 12.7Closing Audit Findings and Recording Results

Understanding HTTP Status Codes

Your roadmap for this lesson

  • What an HTTP status code is and where you see it
  • The five status code classes and what each means for SEO
  • The codes you will meet most often in audits
  • How to check a single URL's status code

Short answer

An HTTP status code is the three-digit reply a server sends for every URL request. For SEO, 2xx means the page loaded, 3xx means it redirects, 4xx means it is missing or blocked, and 5xx means the server failed. Search engines use these codes to decide what to crawl, index, or drop.

Every time Googlebot or a visitor asks for a page, the server replies with a short code before sending anything else. Think of it as the guard at a subdivision gate: “Go in,” “They moved to Block 5,” “No such house,” or “Gate closed, come back later.” That reply is the HTTP status code.

The five classes

ClassMeaningSEO effect
1xxInformationalRarely seen in audits
2xxSuccessPage can be indexed
3xxRedirectSignals pass to the target URL
4xxClient errorPage treated as missing, eventually dropped
5xxServer errorCrawling slows, long outages can drop pages

The codes you will see most

  • 200 OK: The page loaded. This is what indexable pages should return.
  • 301 Moved Permanently / 308: Permanent redirect. Google moves signals to the new URL.
  • 302 Found / 307: Temporary redirect. Google may keep the old URL indexed for a while.
  • 404 Not Found: The page does not exist.
  • 410 Gone: Removed on purpose, will not return.
  • 403 Forbidden: Access refused, often by a firewall or permissions.
  • 500 Internal Server Error: The server crashed while building the page.
  • 503 Service Unavailable: Temporary outage or maintenance.

Where to see status codes in an audit

In your crawler, the Response Codes tab groups every URL by status. Filter by class to find redirects, client errors, and server errors. For one URL, use Search Console’s URL Inspection or a browser extension. Always check the code Googlebot gets, not just what your browser shows, since firewalls and caching can treat them differently.

Practice: which class is it?

Sort each item into the right group.

  • 200 OK

  • 301 Moved Permanently

  • 404 Not Found

  • 503 Service Unavailable

  • 410 Gone

  • 307 Temporary Redirect

  • 500 Internal Server Error

Common mistakes

  • Treating every 404 as an error. Removed pages should 404. Broken links to them are the problem.
  • Checking codes only in a browser. Googlebot may get a different response.
  • Ignoring 3xx counts. A crawl full of redirects means internal links need updating (Lesson 3.5).
1. Which code should an important indexable page return?
2. What does a 503 tell Google?
3. A page was removed on purpose and will never return. Which code fits best?

Your action

Next, you will find 4xx errors and the broken links that point to them.

Key terms

HTTP status code
A three-digit number the server returns with every response, describing whether the request succeeded, moved, or failed.
Response header
Information the server sends before the page content, including the status code, redirect location, and caching rules.
410 Gone
A status code saying the page was removed on purpose and will not return. Google may drop it slightly faster than a 404.
503 Service Unavailable
A temporary server error, often used during maintenance, telling crawlers to come back later.

Questions beginners ask

Which status code should a normal page return?

200 OK. Any important page that returns something else needs a reason, such as a planned redirect.

Is a 404 bad for SEO?

Not by itself. Removed pages should return 404 or 410. Problems start when important pages, internal links, or pages with backlinks return 404.

How can I check one URL's status code?

Use the URL Inspection tool in Search Console, a browser extension like Redirect Path, or your crawler in list mode.

Does Google treat 403 like 404?

Google treats most 4xx codes, including 403, as a sign the content is not available, and eventually drops those URLs from the index.

Related lessons

Want someone to handle SEO for your business while you learn? The team at Remar Digital can help.