The Technical SEO Audit Checklist for 2025

A technical SEO audit is the foundation of any serious SEO strategy. Before investing in content or link building, you need to ensure search engines can actually crawl, index, and understand your site. Missing this step is like pouring water into a leaky bucket.

Below is the checklist we use when auditing sites at Auxmeta, organized by category so you can work through it systematically.

Crawlability & Indexing

The first thing to verify is that Google can access the pages you want ranked and can't access the ones you don't. Misconfigured robots.txt files and accidental noindex tags are surprisingly common, even on mature websites.

• Verify robots.txt allows crawling of important pages
• Check for accidental noindex on key pages
• Confirm canonical tags point to the correct URLs
• Ensure XML sitemap is submitted and up-to-date
• Check crawl budget on large sites (1000+ pages)

Site Architecture

Good site architecture means every important page is reachable within a few clicks from the homepage. Orphan pages—pages with no internal links—are effectively invisible to both users and search engines.

• Audit internal link structure for orphan pages
• Ensure important pages are within 3 clicks of homepage
• Fix broken internal links (404s)
• Eliminate redirect chains (keep to one hop max)
• Check for duplicate content across URLs

On-Page Signals

Title tags and meta descriptions remain the most direct signals for both rankings and click-through rates. Missing, duplicate, or truncated titles are low-hanging fruit that most sites can improve quickly.

• Unique, keyword-rich title tags on all pages
• Compelling meta descriptions under 155 characters
• Proper H1-H6 heading hierarchy
• Descriptive alt text on all images
• Structured data (schema.org) where relevant

Performance & Security

HTTPS is a confirmed ranking signal and a baseline requirement for user trust. Page speed affects both rankings and conversions. Neither should be treated as optional.

• HTTPS enforced with valid SSL certificate
• Core Web Vitals pass Google's threshold
• No mixed content warnings
• Hreflang tags correct for multilingual sites
• Mobile-friendly confirmed via Google's test