The Technical SEO Checklist Every Site Needs

Most websites don't lose rankings because of bad content — they lose them because Google can't crawl, render or trust the site properly. Technical SEO is the layer that makes everything else work. Get it wrong and your best pages stay invisible; get it right and every piece of content you publish has a fair chance to rank. Below is a practical, step-by-step technical SEO checklist — in the order that makes most sense to work through it.

1. Crawlability: can Google actually reach your pages?

Before a page can rank, Googlebot has to be able to fetch it. The fastest way to lose rankings is to accidentally block crawling. Start by checking your robots.txt — it should allow your important routes and only disallow genuinely private areas like/api/ or build internals. A single stray Disallow: / can deindex an entire site overnight.

Next, look at your internal link structure. Google discovers pages by following links, so any page that isn't linked from somewhere is effectively an “orphan” — it may never be found. Every important page should be reachable within three clicks of the homepage. Navigation, footers and contextual in-content links all count.

• Confirm robots.txt allows your key sections and references your sitemap.
• Run a crawl (Screaming Frog, Sitebulb or the free Google Search Console URL Inspection) and look for orphan pages.
• Fix broken internal links and redirect chains — each hop wastes crawl budget.
• Make sure pagination and faceted filters don't generate thousands of low-value URLs.

2. Indexation: is Google keeping the right pages?

Crawling is permission to look; indexing is the decision to store and rank. The two most common indexation mistakes are blocking pages you want indexed and indexing pages you don't. Both quietly erode performance.

Use the noindex meta robots tag deliberately — on thank-you pages, internal search results and staging URLs — and never on money pages. In Google Search Console, the Pagesreport tells you exactly what's indexed and why something isn't. “Crawled — currently not indexed” usually means thin or duplicate content; “Discovered — currently not indexed” usually means crawl-budget or quality issues.

3. Canonical tags: one URL per piece of content

Duplicate content is rarely malicious — it's usually ?utm= parameters, trailing slashes, HTTP vs HTTPS, or www vs non-wwwall serving the same page. Google has to pick one version to rank, and if you don't tell it which, it guesses — often wrong. A self-referencing canonical tag on every page removes the ambiguity.

Rule of thumb: every indexable page should point its canonical at its own clean, absolute URL — and that URL should appear in your sitemap.

Watch for the classic bug where a shared layout sets one canonical for many child pages. If your framework merges metadata from a parent layout, a single hard-coded canonical can silently leak onto dozens of pages, telling Google they're all duplicates of one URL.

4. XML sitemaps & robots.txt working together

Your sitemap is the list of URLs you want indexed; robots.txt is the set of areas you don't want crawled. They should never contradict each other. A page that is disallowed in robots.txt but present in the sitemap sends a confusing signal.

• Include only canonical, indexable, 200-status URLs in the sitemap.
• Keep it current — stale sitemaps with dead URLs reduce trust.
• Reference the sitemap from robots.txt (Sitemap: https://example.com/sitemap.xml).
• Submit it in Google Search Console and monitor the coverage report.

5. Structured data: help Google understand context

Schema markup (JSON-LD) doesn't directly boost rankings, but it dramatically improves how your pages are understood and displayed. The right schema can earn rich results — star ratings, FAQs, breadcrumbs, article bylines — that lift click-through rate even at the same position.

For an agency or business site, the high-value types are Organization,WebSite, BreadcrumbList, Service, FAQPage andBlogPosting. Always validate with Google's Rich Results Test, and make sure the structured data matches what's actually visible on the page — mismatches can trigger manual actions.

6. Core Web Vitals: speed is a ranking signal

Google's Core Web Vitals are confirmed ranking factors and, just as importantly, they correlate strongly with conversions. There are three to track:

• LCP (Largest Contentful Paint) — how fast the main content loads. Aim for under 2.5s. Optimise images, preload the hero, and serve from a CDN.
• INP (Interaction to Next Paint) — responsiveness to taps and clicks; it replaced FID. Aim for under 200ms by trimming long JavaScript tasks.
• CLS (Cumulative Layout Shift) — visual stability. Aim for under 0.1 by setting explicit width/height on images and reserving space for embeds.

Measure field data (real users) in the Search Console Core Web Vitals report, not just lab tools like Lighthouse. Lab scores are a useful proxy, but Google ranks on what real visitors experience.

7. Mobile, HTTPS & the non-negotiables

Google indexes the mobile version of your site first, so your mobile experience is your SEO. Confirm responsive layouts, tappable targets, and no content hidden from mobile crawlers. HTTPS is mandatory — an expired or misconfigured certificate can tank trust and rankings. And make sure your hreflang tags (if you serve multiple regions or languages) point to valid, reciprocal URLs.

Frequently asked questions

How often should I run a technical SEO audit?

A full audit quarterly is a sensible baseline, with a lighter monthly check of Search Console's coverage and Core Web Vitals reports. Always run one after a major site migration, redesign or framework change — those are when crawl and canonical bugs sneak in.

Does technical SEO alone get me to page one?

No — and any agency that promises that isn't being honest. Technical SEO removes the barriers that stop you ranking, so Google can crawl, index and trust your pages. Actually ranking on competitive terms still needs strong content and authoritative backlinks over time. Think of technical SEO as the foundation: necessary, but not sufficient on its own.

What's the single most common technical SEO mistake?

Accidental noindex or Disallowrules left over from staging. It happens constantly — a site launches with the “discourage search engines” setting still on, and weeks pass before anyone notices traffic never arrived. Always verify indexability on launch day.

The bottom line

Technical SEO isn't glamorous, but it's the highest-leverage SEO work you can do — because it compounds. Every barrier you remove makes all your future content rank better. Run this checklist top to bottom, fix what you find, and re-check after every major change.

Need a second pair of eyes? Talk to our team— we can audit your site and tell you, in plain language, what's holding it back.