Every site we audit fails at least a few of the same checks. Not because the owners are careless, but because nobody ever handed them the list. This is that list: the technical SEO checklist we work through on real client audits, in the order we run it, with a plain-English reason for every item. Work through it top to bottom and you will find the problems that matter before they cost you rankings. If you want the background first, start with our guide to what technical SEO is, then come back here to run the checks.
Step 0: get the data before you judge anything
A technical SEO checklist is only as good as the data behind it, so start by opening two dashboards. Google Search Console is Google telling you directly which pages it has indexed, which it has excluded, and what errors it hit. PageSpeed Insights gives you Core Web Vitals from real Chrome users. Then run a crawler such as Screaming Frog, free for up to 500 URLs, which reads your site the way Googlebot does and lists every broken link, redirect and duplicate in one export.
With those three sources open, everything below stops being guesswork. You are ticking items off against evidence, which is the difference between a technical SEO audit and a vibe check. It also makes the work repeatable: the next time you run the technical SEO checklist, you can compare results against the last export and see exactly what changed, and what a plugin update or redesign quietly broke.
Crawlability and indexing checks
These come first because they can block rankings outright. One stray tag here outweighs everything else on the technical SEO checklist combined.
Check that your important pages are indexable: no accidental noindex tags, and no disallow rules in robots.txt covering sections you want ranked. Check the Pages report in Search Console for anything important sitting in the excluded list. Confirm your XML sitemap exists, is submitted, and lists only live, indexable URLs. Verify each page has one canonical version: www or non-www, trailing slash or not, with everything else redirecting to it. And make sure no key page returns a server error or lives more than a few clicks from the homepage.
Online stores get one extra check here: filtered and sorted category URLs. Every combination of size, colour and price filter can mint a new URL, and left unmanaged they multiply into thousands of near-duplicates that swamp the pages you actually want crawled.
Site speed and Core Web Vitals
Next on the technical SEO checklist is performance, because it affects every page at once. Run your key pages through PageSpeed Insights and look at the field data, the measurements from real users. You are aiming to pass Core Web Vitals: main content loading within 2.5 seconds, response to interactions within 200 milliseconds, and minimal layout shift while the page loads.
If you fail, the fixes are usually unexciting: compress and resize images, remove plugins you no longer use, defer scripts that are not needed immediately, and upgrade hosting if the server itself is slow. Check the mobile numbers first. Most of your visitors are on phones, and so is Google.
Prioritise by blast radius. A slow template affects thousands of pages; a broken link affects one. When two items on the checklist compete for your time, fix the one that touches the most pages first.
Redirects, broken links and duplicates
Your crawl export earns its keep in this part of the technical SEO checklist. Fix or remove every internal link that points at a 404, starting with pages that still earn traffic or have backlinks. Give every deleted or moved URL a proper 301 redirect to its closest living equivalent. Flatten redirect chains, where A points to B points to C, so every redirect lands in one hop. And check for duplicate title tags and meta descriptions, which usually reveal duplicate or near-duplicate pages competing with each other.
None of these items is dramatic on its own. Together they decide how efficiently authority flows around your site, and the site health scores most audit tools report are largely a reflection of this section. Work through it methodically; this is the stretch of the technical SEO checklist where steady beats clever.
Structured data, mobile and security
The last section of the technical SEO checklist covers the trust and clarity layer. Confirm the whole site loads over HTTPS, with the http version redirecting. Check the site is genuinely usable on a phone: readable text, tappable buttons, nothing hidden or overflowing. Validate your structured data with Google's Rich Results Test so machines can read who you are, what you sell and what each page is. And review your image handling: descriptive file names, alt text on meaningful images, and lazy loading below the fold. None of these will rescue a site that fails the earlier sections, but together they are the difference between a site Google merely tolerates and one it trusts.
How often to run the technical SEO checklist
A technical SEO audit is not a one-time event, because websites drift. Plugins update, staff delete pages, a redesign quietly changes URLs. For most small business sites, a full pass through this technical SEO checklist once a quarter is enough, with a quick Search Console review monthly. Large sites and online stores should check monthly. And any migration, redesign or CMS change gets a full audit before and after, no exceptions; that is where the worst damage we see comes from. Our guide to running a full SEO audit shows how the technical pass fits into the bigger picture of content and authority.
If the list turned up more red than you expected, that is normal, and it is fixable. This is exactly what our technical SEO service does week in, week out: the same technical SEO checklist, run with better tools and more reps, then crawl, diagnose, fix and verify in priority order.
Want the technical SEO checklist run for you? Talk to us and we'll deliver the full technical review with every check completed and a prioritised fix list attached.
