The Technical SEO Checklist for a New Website

None of SEO matters if search engines cannot reach your content. Crawlability is the foundation everything else sits on, and it fails in embarrassingly common ways: JavaScript-rendered pages with no server-side rendering that crawlers see as blank, robots.txt files carried over from staging that block the entire site, and navigation built so deep that important pages sit five clicks from the homepage.

Start with the mechanics. Your robots.txt should allow crawling of everything you want indexed and block only what you don't, admin areas, API routes, internal search result pages. Your XML sitemap should list every indexable URL, stay under the 50,000-URL and 50MB limits per file, and be referenced in robots.txt and submitted in Search Console. Then check the reality with a crawl of your own: tools like Screaming Frog show you exactly what a crawler encounters, including the pages you forgot existed.

Internal linking is the part most sites underinvest in. Every important page should be reachable within three clicks of the homepage through contextual links, not just navigation menus, but links inside your content where they naturally help the reader. Internal links distribute authority across your site and tell Google which pages you consider important. A page with no internal links pointing to it is a page you have told Google not to care about.

Being crawlable is only half the job; you must also control what gets indexed. Every duplicate or thin page in the index dilutes the authority of pages that matter. The classic offenders: HTTP and HTTPS versions both live, www and non-www both live, trailing-slash variants, UTM-parameter URLs, and paginated or filtered pages each indexed separately.

Canonical tags are your primary tool. Every page should self-canonicalize, and duplicate variants should canonicalize to the preferred version. This is a hint, not a command, Google usually honors it, but the cleaner your URL structure, the less you rely on hints. Pick one canonical domain (we recommend www or apex, not both) and redirect the other with a proper 301.

Use noindex deliberately for pages that serve users but shouldn't rank: thank-you pages, internal search results, login and cart pages, staging environments. And audit index bloat quarterly with a site: search or Search Console's coverage report. If Google is indexing hundreds of tag or filter pages you never meant to rank, your crawl budget is being spent in the wrong place.

Page experience is a confirmed ranking signal and a conversion lever, so technical SEO and performance work overlap heavily. The targets: Largest Contentful Paint under 2.5 seconds, Interaction to Next Paint under 200 milliseconds, Cumulative Layout Shift under 0.1, measured on real field data for your actual visitors, not just lab tests.

The highest-ROI fixes are unglamorous. Serve images in modern formats at responsive sizes with explicit dimensions. Cut third-party scripts to what earns its place. Ensure your most important pages are server-rendered or statically generated so crawlers and users get content immediately, not after JavaScript executes. Client-side-rendered SPAs remain the single most common technical SEO failure we encounter.

Mobile is not a separate checklist anymore, Google indexes mobile-first, so your mobile experience is your SEO experience. Test on mid-range devices and throttled networks, because that is where your rankings are actually decided.

Structured data doesn't directly boost rankings, but it unlocks rich results, star ratings, FAQ dropdowns, event details, product prices, that dramatically raise click-through rates from the same ranking position. A result with rich snippets can out-earn the position above it, which is as close to free traffic as SEO gets.

Prioritize by page type. Organizations get Organization schema with logo and contact info. Blog posts get BlogPosting with author, dates, and images. Service pages get Service schema. FAQs get FAQPage, but only for visible on-page FAQs, since Google penalizes markup for hidden content. Products get Product with offers and reviews. Breadcrumbs get BreadcrumbList, which also improves how your URLs display in results.

Validate everything in Google's Rich Results Test before launch and monitor Search Console's enhancements reports after. Broken or misleading schema is worse than none: it erodes the trust signals you're trying to build. Keep the markup in sync with visible content, schema that contradicts the page is a spam signal.

Two weeks before launch, run the full pass in order. Crawl the staging site and fix broken links, redirect chains, and 404s. Verify robots.txt and meta robots allow indexing on production (and that staging remains blocked). Confirm the sitemap generates correctly and canonicals point at production URLs, not staging ones, staging URLs in canonicals are a classic launch-day disaster.

On launch day: submit the sitemap in Search Console, request indexing for key pages, and verify analytics and Search Console are collecting. Set up 301 redirects for every URL that changed, rank equity transfers through proper redirects, and broken backlinks from the old structure are link equity thrown away.

In the first month, watch Search Console like a hawk: coverage errors, Core Web Vitals field data as real traffic arrives, and the performance report for early query impressions. Most launch issues surface within two weeks, and the faster you fix them, the less ranking momentum you lose. Technical SEO is never finished, but a disciplined launch puts you months ahead of sites that treat it as an afterthought.