Technical SEO Audit: What to Check and How to Fix It

Technical SEO problems don't fail loudly. A misconfigured canonical tag doesn't throw an error — it just quietly prevents your pages from ranking, and you notice weeks later when traffic doesn't come. This audit covers the issues most likely to be actively hurting your site.

1. Crawlability and Indexation

Start in Google Search Console > Coverage > Errors. Any page showing as 'Excluded' or 'Error' needs investigation. Check: robots.txt isn't accidentally blocking important pages (fetch robots.txt directly to verify). Noindex tags aren't on pages you want indexed. Canonical tags on each page point to themselves, not to some other URL.

The canonical tag mistake to watch for: if your root layout has a canonical tag, it may bleed to all child pages, telling Google every page on your site is an alternate version of your homepage. This kills indexation across the board. Each page.tsx must define its own self-referencing canonical.

2. Site Architecture and Internal Linking

Every important page should be reachable within 3 clicks from the homepage. Pages buried 6 levels deep get crawled rarely and often poorly indexed. Use Google Search Console's URL Inspection tool to check when Googlebot last crawled specific pages — pages crawled more than 30 days ago may have site architecture problems preventing regular crawling.

3. Core Web Vitals

• LCP (Largest Contentful Paint): Should be under 2.5 seconds. Usually caused by unoptimized hero images or render-blocking resources.
• INP (Interaction to Next Paint): Under 200ms. Caused by heavy JavaScript executing on main thread.
• CLS (Cumulative Layout Shift): Under 0.1. Common cause: images without explicit dimensions, ads loading above content.

4. Structured Data

Schema markup doesn't directly boost rankings, but it helps Google understand your content and enables rich results (FAQ accordions, review stars, how-to steps). Validate your structured data with Google's Rich Results Test. Common implementations worth having: Article schema on blog posts, FAQPage for FAQ sections, HowTo for step-by-step guides, and WebApplication for online tools.

5. Duplicate Content

Duplicate content dilutes ranking signals. Common sources: www vs non-www versions (use redirect + canonical), HTTP vs HTTPS (always redirect to HTTPS), trailing slashes (/page vs /page/), URL parameters creating duplicate pages (/products?color=red and /products?color=blue showing identical content). Fix with canonical tags and proper redirects.