Technical SEO Checklist Before You Launch a Website

Most SEO damage happens on launch day: a leftover noindex tag, missing redirects, or a staging domain in the canonical tags. This technical SEO checklist takes about an hour to run and prevents the mistakes that take months to recover from.

1. Indexing and crawling

• Remove any noindex tag and password protection used during development.
• Check robots.txt: it must not block the whole site, CSS or JavaScript.
• Make sure every important page returns status 200, and missing pages return a real 404, not a 200 with an error message.
• Keep staging and test domains blocked or behind a password so they are never indexed.

2. Redirects from the old site

If you are replacing an existing site, this is the most important item on the technical SEO checklist.

• Map every old URL that has traffic or backlinks to its closest new page with a 301 redirect.
• Do not redirect everything to the homepage.
• Avoid redirect chains: old URL to final URL in one step.
• Test the list after launch with a crawler.

3. URLs, canonicals and duplicates

• One address per page: choose https and either www or non-www, and redirect the others.
• Each page has a self-referencing canonical tag pointing to the live domain.
• Filter, sort and tracking parameters do not create indexable duplicates.
• Trailing slashes are consistent.

4. Titles, descriptions and headings

• Every page has a unique title of roughly 50 to 60 characters and a unique meta description.
• One H1 per page, followed by logical H2 and H3 headings.
• Images that carry meaning have alt text.

5. Sitemap and Search Console

• Generate an XML sitemap containing only indexable, canonical URLs.
• Reference it in robots.txt and submit it in Google Search Console.
• Verify the domain property so you see data for all protocol and subdomain variants.

6. Structured data

Add the types that match your content: Organization or LocalBusiness, Product with price and availability, Article, BreadcrumbList and FAQPage where a real FAQ exists. Validate with the Rich Results Test. Only mark up what is visible on the page.

7. Speed and mobile

• Test the main templates on a phone, not just on a desktop.
• Compress and size images, set width and height, and lazy-load those below the first screen.
• Check loading, responsiveness and layout stability; see Core Web Vitals explained.

8. International and multilingual sites

• Each language has its own URL.
• hreflang tags link equivalent pages in both directions and include a self-reference.
• Do not redirect visitors automatically by IP; offer a language switch instead.

9. Security and basics

• A valid HTTPS certificate with no mixed-content warnings.
• A custom 404 page with navigation and search.
• A favicon, and Open Graph tags so shared links look right.

10. Tracking

• Analytics installed once, not twice.
• Conversions defined: form submissions, calls, purchases.
• Internal traffic filtered where possible.
• Record a baseline on day one so you can measure growth.

After launch

In the first two weeks, watch Search Console daily: coverage errors, pages "crawled but not indexed" and 404s from old links. Fix them as they appear. A short dip is normal after a migration; a continuing decline means something on this list was missed.

If you would rather have this handled for you, see our SEO service and the complete SEO guide.

Summary

A technical SEO checklist is cheap insurance. Check indexing, redirects, canonicals, titles, sitemap, structured data, speed, hreflang, security and tracking before launch, then monitor Search Console for two weeks.

FAQ

What is the most common launch mistake? Leaving the development noindex tag in place, followed by missing redirects from old URLs.

Do I need a sitemap for a small site? It is not required, but it helps search engines find new pages faster and costs nothing.

How soon will a new site appear in Google? Usually within days after the sitemap is submitted, but ranking for competitive terms takes months of content and links.