Technical SEO checklist: the 25 things that actually matter

SEO audits love volume: 200 items that make the report look serious and the work look unbounded. The reality: about 25 technical factors do almost all the ranking work. Here's the list we run on our own builds, grouped by what it does for you.

The checklist at a glance

Fix strictly in tier order: a page Google can't reach doesn't benefit from a faster LCP.

Tier 1: Can Google get the page at all?

1. 01Pages return 200, not 404/soft-404/redirect-chains
2. 02robots.txt isn't blocking what should be indexed
3. 03No accidental noindex on pages that should rank
4. 04Every indexable page is in the XML sitemap
5. 05Sitemap is submitted in Search Console and referenced in robots.txt
6. 06Content is in the HTML on first paint, not injected by client-side JS
7. 07HTTPS everywhere; one canonical host (www or non-www, not both)

Tier 2: Does Google understand the page?

1. 01Unique, descriptive <title> per page (~50–60 chars)
2. 02Unique meta description per page (~150–160 chars)
3. 03One clear H1; headings form a real outline
4. 04Canonical tag on every page pointing at the right URL
5. 05Structured data where it fits: Organization, Service, Article, BreadcrumbList, FAQ
6. 06Descriptive internal links: the page gets linked from pages Google already trusts
7. 07Clean URLs: short, readable, keyword-bearing (/services/web-development, not /p?id=47)

Tier 3: Does it perform?

1. 01LCP under ~2.5s (the big contentful paint: hero image/text)
2. 02CLS near zero: no layout jump while loading
3. 03Images compressed, correctly sized, lazy-loaded below the fold
4. 04Fonts loaded efficiently (display: swap, limited weights)
5. 05Minimal third-party scripts: every tag manager and chat widget taxes everything else
6. 06Mobile layout works, real mobile-first, not a desktop page squeezed

Tier 4: The hygiene that prevents silent damage

• 404s handled gracefully (custom page, not a dead end)
• Redirects are 301/308, single-hop, and old URLs still resolve
• Trailing-slash and casing consistency: /services not /Services and /services/
• No orphan pages: every page reachable by links
• OG/Twitter cards present so shared links look right

How to actually run this checklist

1. 01Start in Search Console: Pages report shows exactly what isn't indexed and why, fixing those reasons is most of Tier 1.
2. 02Fetch a key page with JavaScript off (or curl it): if the content isn't in the HTML, Tier 1 has a rendering problem.
3. 03Run PageSpeed Insights on your three highest-value templates: homepage, a service/product page, a content page.
4. 04View source on five pages: check title, meta description, canonical and H1 are present and unique.
5. 05Crawl-check internal links: every important page should be reachable in two or three clicks from the homepage.

For agencies and multi-site teams

Running this once isn't a checklist, it's an audit. What makes it a checklist is repeatability: a fixed baseline run on every new build, a quarterly regression pass on existing sites, and a per-client record of which tier each fix belongs to so nothing gets re-diagnosed twice. The agencies that win retainers on technical SEO are the ones with a boring, repeatable version of this exact list.

How we handle it

Every build we ship, including this site, gets all four tiers by default: static-prerendered pages, per-route metadata, canonicals, sitemap, JSON-LD, Web-Vitals-budgeted images and fonts. It's cheaper to build it in than to audit-and-patch later.