Technical SEO Audit: Complete Guide

A technical SEO audit is a focused review of the underlying infrastructure of your website — crawlability, indexability, site structure, speed and markup — that determines whether search engines can find, understand and rank your pages at all. Even great content can underperform if technical problems get in the way.

Why technical SEO comes first

On-page content and technical foundations work together, but if search engines cannot crawl or index a page, its content quality is irrelevant. That is why technical checks are usually the starting point of any wider SEO audit.

Crawlability

Search engines need to be able to reach your pages before they can evaluate them. Check:

• Your robots.txt file is not blocking sections of the site by mistake
• Internal links connect all important pages, so nothing is orphaned
• Your site does not rely on navigation that crawlers struggle to follow

Indexability

Being crawlable is not the same as being indexable. Review:

• Robots meta tags and X-Robots-Tag headers on individual pages, to confirm important pages are not set to noindex accidentally
• Canonical tags, checking they point to the intended version of each page rather than conflicting with each other
• Your XML sitemap, making sure it reflects your current page set and does not list removed or redirected URLs

HTTPS and redirects

Confirm your entire site runs on HTTPS, not just selected pages, and that any HTTP versions redirect properly. Audit your redirects for chains (multiple hops before reaching the final page) and loops, both of which waste crawl budget and slow down users. A HTTP status tool is useful for spotting unexpected status codes on key URLs.

Site speed and Core Web Vitals

Technical performance affects both user experience and search visibility. Google's Core Web Vitals — Largest Contentful Paint, Interaction to Next Paint and Cumulative Layout Shift — are field metrics that reflect real user experience. Our Core Web Vitals guide covers the current thresholds in detail. You can check your own pages with a page speed tool, which draws on Google PageSpeed Insights data where available.

Structured data

Structured data (schema markup) helps search engines understand the type of content on a page, such as articles, products or local business details. Checking for its presence across key pages is a standard part of a technical audit, even though structured data itself does not guarantee any particular search feature.

Mobile and rendering

Since most search traffic is mobile, confirm your pages include a proper mobile viewport meta tag and render correctly on smaller screens. Pages that require pinching and zooming, or that hide content behind broken layouts, create both a user experience and technical SEO problem.

Running a technical check

You can check many of these items in one pass using an automated tool. SiteScore's technical SEO checker crawls a sample of up to 6 pages from your homepage and sitemap and checks titles, meta descriptions, headings, canonicals, robots meta and X-Robots-Tag, robots.txt, your XML sitemap, internal links, broken links within the sample, HTTPS and redirects, structured data presence, Open Graph tags, image alt text and mobile viewport configuration. Page speed data comes from Google PageSpeed Insights where it is available. It does not measure your search rankings, traffic or backlinks, so pair it with your analytics and search console data for the full picture.

Turning findings into fixes

Technical issues vary a lot in effort to fix. Missing alt text or a stray noindex tag might take minutes to correct, while restructuring redirects across a large site or improving speed on a slow platform can take much longer. Start with anything blocking indexing entirely, since that has the biggest possible impact, then work through speed and markup issues. ## Common technical issues found in audits

Certain problems show up repeatedly across different sites:

• Pages accidentally set to noindex after a site migration or redesign
• Sitemaps that still list old or redirected URLs
• Mixed HTTP and HTTPS content causing browser warnings
• Redirect chains left over from previous URL changes
• Missing or duplicate canonical tags across similar pages

Technical SEO and site migrations

Site migrations, whether a redesign, a platform change or a domain move, are one of the highest-risk moments for technical SEO. URLs can change, redirects can be missed, and sitemaps can go stale almost overnight. Running a technical audit both before and shortly after a migration helps catch problems while they are still easy to fix, rather than weeks later once visibility has already been affected.

Working with developers

Many technical SEO fixes require developer involvement, particularly around redirects, server configuration and rendering behaviour. Framing issues clearly — what the problem is, which pages it affects, and why it matters — makes it easier for a development team to prioritise the work alongside other tasks. Where possible, attach specific examples rather than general statements, since concrete evidence speeds up fixes.

Next step

Check your site's technical foundations now with SiteScore's technical SEO checker.