On-Page SEO Audit

404s, 4xx/5xx, DNS, SSL (errors + expiring certs), timeouts, connection refused, robots.txt unreachable, soft-404, custom 404 returning 200.

Chains, loops, mixed 301/302, internal-via-redirect, trivial, HTTPS→HTTP downgrade, meta refresh, entry URL leaving the site.

Empty/placeholder/javascript hrefs, missing fragment targets, duplicate element IDs, empty resource srcs.

rel=noopener missing (tabnabbing), rel=nofollow on internal links, external links with no rel at all.

Anchor text, mixed content, UTM, duplicates, invalid mailto/tel/URL, long URLs, staging/dev URLs leaked into production, protocol-relative and lingering http:// links, resource Content-Type mismatches.

Canonical mismatch/multiple/relative/chain/noindex-target/broken, robots-blocked internal links.

Title, meta description, H1, heading order, viewport (incl. device-width), Open Graph and og:image reachability, Twitter Card, favicon, charset, RSS/Atom feed.

Invalid locales, missing self-reference, missing x-default, missing return tags, duplicates, relative hrefs, lang mismatches, error targets.

Image alt, form labels, button text, iframe titles, empty headings, main landmark, tabindex, video captions, html lang (presence + BCP-47), zoom-disabling viewport.

Title=description, URL underscores, URL params, meta keywords, JSON-LD structured data.

Heavy HTML, missing image dimensions, missing compression, missing Cache-Control, slow page response, oversized images.

Missing CSP, weak CSP (unsafe-inline/unsafe-eval), HSTS, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, insecure cookies, missing SRI.

Thin content, paginated URLs without rel=prev/next.