How to Do a Technical SEO Audit: A Step-by-Step Guide

A technical SEO audit checks whether search engines can crawl, render, index and understand your pages, and whether those pages load quickly and work well for real visitors. Run it in this order: indexing, crawling, status codes and redirects, canonicals and duplicates, site structure, speed, mobile, structured data and JavaScript. Then rank the fixes by their effect on the pages that bring you customers.

What You Need

• Google Search Console, verified for the whole domain.
• A crawler. Screaming Frog is the common choice and crawls up to 500 URLs free.
• PageSpeed Insights and Chrome's developer tools.
• Google's Rich Results Test for structured data.
• A list of your most valuable pages, so you judge every issue by what it does to them.

Step 1: Check What Google Has Indexed

Open the Pages report in Search Console. It shows how many pages are indexed and, under "Not indexed", the reason for each group. Look for your important pages among them. Common reasons:

• Excluded by noindex tag: often left over from a staging site.
• Blocked by robots.txt.
• Duplicate without user-selected canonical: Google chose another URL as the main version.
• Crawled, currently not indexed: Google saw the page and decided not to index it, often a sign of thin or duplicate content.
• Not found (404) and soft 404.

Use the URL Inspection tool on a few key pages to see exactly what Google sees.

Step 2: Crawl the Site

Run a full crawl with JavaScript rendering on if your site relies on it. From the crawl, check:

• Status codes: every important page returns 200; no internal links point to 404s or redirects.
• Redirects: each old URL goes to its final destination in one step, with no chains or loops.
• robots.txt: important folders are allowed, and CSS and JavaScript files are not blocked.
• XML sitemap: lists only indexable, canonical URLs that return 200.

Step 3: Canonicals and Duplicate Content

• Each page should have a canonical tag pointing to itself, unless it is a genuine duplicate.
• Check that http, https, www and non-www versions redirect to one version.
• Look for near-duplicates: tracking parameters, sort orders, printer versions, or many pages that differ only by a city name.
• On online stores, check filtered and paginated category URLs, which can create thousands of low-value pages.

Step 4: Site Structure and Internal Links

• Important pages should be reachable within a few clicks of the homepage.
• Find orphan pages that no internal link points to.
• Check that menus and breadcrumbs use real links that a crawler can follow.
• Make sure anchor text describes the page it links to.

Step 5: Speed and Core Web Vitals

Use Search Console's Core Web Vitals report for real-visitor data, and PageSpeed Insights for individual pages. A page is good when, at the 75th percentile, Largest Contentful Paint is 2.5 seconds or less, Interaction to Next Paint is 200 milliseconds or less, and Cumulative Layout Shift is 0.1 or less.

Common causes of poor scores: large uncompressed images, render-blocking scripts, heavy third-party tags, web fonts that load late, and images or ads without reserved space.

Step 6: Mobile

Google states that it uses the mobile version of a site's content for indexing and ranking. Check that:

• The mobile version has the same content, headings, links and structured data as desktop.
• Nothing is wider than the screen, text is readable, and buttons are easy to tap.
• No pop-up covers the content on arrival.

Step 7: Structured Data

Test key templates in the Rich Results Test. Fix errors, and check that the markup matches what the page visibly shows: prices, reviews, FAQs and business details.

Step 8: JavaScript Rendering

If content or links only appear after JavaScript runs, compare the raw HTML with the rendered page (URL Inspection shows the rendered HTML). Key content, links and metadata should be in the HTML the server sends, both for search engines and for AI crawlers, many of which do not run JavaScript.

Step 9: Security and Hygiene

• HTTPS on every page, with no mixed content.
• No hacked content or spam pages (Search Console's Security issues report).
• A custom 404 page that returns a real 404 status.

Step 10: Prioritize and Re-Check

Group what you found:

After fixes go live, re-crawl the site and use URL Inspection to request indexing of the most important changed pages.

A technical audit is one part of a full audit. Our SEO audit checklist adds content, links, local and tracking checks, and our SEO audit does all of it for you in 7 working days.