Technical SEO is the set of adjustments that lets Google access, understand and store your site’s pages. Before paying for new articles, check six things: whether your pages are indexed, whether canonicals and redirects are correct, whether the site loads over HTTPS, whether it passes Core Web Vitals, whether it works well on mobile, and whether Google can read what depends on JavaScript. Good text on a page Google doesn’t list brings no visits at all.
This checklist follows Google Search Central documentation. Search Console and a browser are enough for much of the checking.
What technical SEO is and why it comes before content
Technical SEO is the part of SEO that looks after the site itself, not the text on it. It answers one question: can Google reach this page, read the content and decide to keep it in the index?
Imagine a store that publishes four articles a month for six months. If a “noindex” was left on since development, all 24 articles are working in the dark.
That’s why the order is this: technical SEO audit first, editorial calendar after. To see where this fits in an agency’s work, read what an SEO agency delivers in the first month.
Indexing: has Google stored your pages?
A page outside Google’s index doesn’t show up in any search, no matter how good the text is. It’s the first thing to look at in technical SEO for websites.
Search Console
Google Search Console is the free tool that shows how Google sees your site. Open the page indexing report and check the reason for each URL that was left out. Then use URL inspection on the pages that sell the most: it tells you whether the page is on Google, which canonical Google chose and whether anything blocked access.
robots.txt and noindex
robots.txt is a file at the root of the site that tells bots which areas not to crawl. Noindex is an instruction on the page asking Google not to show it in results. Mixing the two up is a classic mistake.
According to Google, for noindex to work the page must not be blocked by robots.txt. If it is, the bot never reads the noindex and the page can still appear in results, for example when other pages link to it. The details are on Google’s page about blocking indexing.
Two quick checks:
- Open `yoursite.com/robots.txt` and look for a `Disallow: /` alone on a line, which blocks the whole site.
- In WordPress, go to Settings and then Reading, and confirm that “Discourage search engines from indexing this site” is unchecked.
Sitemap
A sitemap is a file that lists the URLs you want indexed. For Google it’s a hint, not an order. Submit it through Search Console and keep it clean: only URLs with a 200 status, no redirects and no noindex.
Canonical, redirects and 404 errors
The canonical tells Google which is the main version of a page that exists at more than one address. Redirects and 404 errors tell it what happened to addresses that changed or disappeared.
Canonical
A page often has several addresses: with and without “www”, with a trailing slash or not, with tracking parameters. Without a clear canonical, Google chooses on its own. Google’s documentation on duplicate URLs recommends using just one method (the link rel=”canonical” in the HTML or the HTTP header), because using both at once increases the chance of error. It also warns against using robots.txt to deal with duplicates.
In URL inspection, compare the declared canonical with the one Google chose. A mismatch on an important page is a problem to fix.
Redirects
When a page moves to a new address permanently, the right setup is a permanent (301) redirect straight to the new address. Common mistakes are chains (A leads to B, which leads to C) and a temporary redirect used for a permanent move. After any migration, run a crawler.
404 errors
A deleted page that returns a 404 is correct: the server is saying it no longer exists. The problem is a “not found” page that responds with a 200 status, the so-called soft 404, or a broken address sent to the home page. Google treats these responses as errors. If the page had visits or links, redirect to the equivalent content. If not, leave the 404.
HTTPS and security
HTTPS is the version of the address that encrypts the connection between the visitor and the site, and it’s the minimum expected of any page. Without it, the browser shows “not secure” before the first line.
The check has four points:
- The certificate is valid and within its expiration date.
- The http address redirects to https in a single step.
- There is only one version of the domain, with or without “www”, and the other redirects to it.
- No file on the page (image, script, font) loads over http, known as mixed content.
Speed and Core Web Vitals
Core Web Vitals are three metrics Google uses to measure the real experience of people opening the page: loading, response to taps and layout stability. Google’s Core Web Vitals documentation defines the thresholds considered good.
- LCP (Largest Contentful Paint) measures loading. Ideally, the largest element on the screen appears within 2.5 seconds.
- INP (Interaction to Next Paint) measures how quickly the page responds to clicks and taps. Google asks for less than 200 milliseconds.
- CLS (Cumulative Layout Shift) measures how much the page shifts on its own while loading. The limit is less than 0.1.
Check your site in the Core Web Vitals report in Search Console, which uses real visitors, or run the page through PageSpeed Insights. A site with little traffic may show up without enough data, and in that case the PageSpeed lab test is the way to go.
In practice, a poor LCP almost always comes from a heavy image at the top, a slow font, or third-party scripts (chat, pixel, map) running before the content. Start with the main image.
Mobile: Google reads the phone version
Mobile-first indexing means Google mainly uses the mobile version to index and rank. Anything that exists only on desktop doesn’t exist to Google.
Open three important pages on your phone and check that the main text is the same as on desktop, that images and structured data appear in both versions, and that buttons and links have room for a finger. Test on regular 4G, not just on the office Wi-Fi.
Structured data
Structured data is JSON-LD code that describes the page to Google in machine language: who the company is, what the address is, what that article is about. It doesn’t guarantee a highlight in the results, but it helps Google understand each page.
On a business site, the basics are the organization (or local business) markup on the home page and the article markup on blog posts. Test with the Rich Results Test and check the enhancement reports in Search Console. The most common mistake is marking up something that doesn’t appear on the page, like reviews nobody can see.
JavaScript crawling
If the content only appears after a script runs, Google has to execute that JavaScript to see it. A site built with React, Vue, or a builder that assembles the page in the browser falls into this case.
Google crawls, renders, and only then indexes. According to the JavaScript documentation, it doesn’t render files or pages blocked by robots.txt. Blocking the scripts folder can leave Google with an empty page.
How to check:
- In URL Inspection, test the live URL and look at the rendered HTML. The main text needs to be there.
- Confirm that navigation links are real links (`<a>` elements with href), and not buttons that only work on click.
- Check that the title, description, and canonical are in the initial HTML.
- Make sure no script or stylesheet is blocked in robots.txt.
Technical SEO in one table: problem, how to spot it, and what to do
The table sums up the technical SEO checklist, in the order worth working through it.
| Problem | How to spot it | What to do |
|---|---|---|
| Important pages missing from the index | Page indexing and URL Inspection | Read the reason, remove the block, and request indexing again |
| General Disallow or forgotten noindex | Open /robots.txt and the WordPress visibility option | Remove the block from the pages that should appear |
| Sitemap with broken or redirected URLs | Sitemap errors in Search Console | Keep only URLs that return 200, are indexable, and are canonical |
| Canonical different from the one Google chose | URL Inspection | Adopt one method and point to the main version |
| Redirect chain or 302 on a permanent move | Site crawler | Replace with a single 301 straight to the final address |
| Soft 404 or 404 sent to the home page | Page indexing report | Return a real 404 or redirect to the equivalent content |
| Expired certificate or mixed content | Browser padlock and console | Renew the certificate and change http to https |
| LCP above 2.5 s, INP above 200 ms, or CLS above 0.1 | Core Web Vitals and PageSpeed Insights | Compress the top image, defer third-party scripts, set fixed image sizes |
| Different content on mobile and desktop | Pages opened on a phone and URL Inspection | Match text, images, and structured data |
| Structured data with errors | Rich Results Test | Fix the JSON-LD to reflect only what is on the page |
| Content that only appears with JavaScript | Rendered HTML in URL Inspection | Put the main content in the initial HTML and unblock scripts |
What order to fix things in
In technical SEO, start with what keeps Google from seeing the site: indexing blocks, wrong canonicals, and server errors. Redirects, HTTPS, and speed come next, and structured data and fine-tuning for mobile come last.
Change one thing at a time and write down the date, so you know which change moved the Search Console report. And don’t produce new content while an indexing block is still open.
With the right foundation, your content works harder. The article on how to get your business to show up on Google shows the way from there. If you serve customers in a specific city, look at local SEO, and if you want to be cited in AI answers, the next step is in SEO for AI.
Frequently asked questions
What is technical SEO? It’s the set of infrastructure adjustments that lets Google crawl, render, and index your pages: robots.txt, sitemap, canonical, redirects, HTTPS, speed, mobile, structured data, and JavaScript.
What’s the difference between technical SEO and on-page SEO? Technical SEO covers how the site works for search bots. On-page SEO covers the content of each page: title, description, subheadings and text. Technical comes first.
How do I know if Google has indexed my pages? Use the URL Inspection tool in Search Console for a single page and the Page indexing report for the whole site. Typing `site:yourdomain.com` into Google gives you a rough idea, but it doesn’t replace the tool.
What speed thresholds does Google consider good? According to Google’s documentation, LCP within 2.5 seconds, INP under 200 milliseconds and CLS under 0.1.
Do I need a developer for a technical SEO audit? To check, no: Search Console and a browser cover a lot of it. To fix canonicals, bulk redirects, speed and JavaScript, usually yes.
Request a technical analysis of your site
If you’d rather have someone check these points on your domain, message Ciclicko on WhatsApp and ask for an SEO analysis.