Technical SEO checklist: what your website needs

What is technical SEO?

SEO roughly has three parts. Content: your copy and the questions you answer. Authority: how well known and trusted other sites find you, for example through links. And technology: whether Google can search your site without problems. That searching is called crawling. Adding pages to Google's index is called indexing.

So technical SEO is the foundation. If you want the bigger picture, first read what SEO is. Below is the checklist, split into five sections.

Technical SEO checklist 1: can Google find and index your pages?

• Connect your website to Google Search Console. This free Google tool shows which pages are indexed and where the problems are.
• Check the page indexing report. Are important pages marked as 'not indexed'? Find out why.
• Look at your robots.txt. This file tells search engines which parts of your site they may not crawl. One wrong rule can block your whole site. You find it at yourdomain.com/robots.txt.
• Look for a noindex tag on pages that should be found. This often happens by accident after a launch, when a test setting was left on.
• Make sure you have an XML sitemap: a list of all your important pages. Submit it through Search Console.

Checklist 2: speed and Core Web Vitals

Google measures how fast and stable your pages load for real visitors. This is called Core Web Vitals. There are three metrics with fixed thresholds for a good score:

• LCP (Largest Contentful Paint): how fast the largest visible element loads. Good is under 2.5 seconds.
• INP (Interaction to Next Paint): how fast the page responds to a click or tap. Good is under 200 milliseconds.
• CLS (Cumulative Layout Shift): how much the page shifts while loading. Good is under 0.1.

You can see the scores in Search Console and in Google's PageSpeed Insights. Common causes of poor scores are images that are too large, lots of external scripts and slow hosting. You can read more in our articles on Core Web Vitals and making your website faster.

Checklist 3: mobile, secure and accessible

• Does your site work well on a phone? Google mainly looks at the mobile version of your site. Text should be readable without zooming and buttons should be big enough to tap.
• Does your whole site run on https? You then see a padlock in the address bar. Also check that http addresses redirect to https automatically.
• Does your site resolve to one version? yourdomain.com and www.yourdomain.com should lead to the same version, not both be reachable separately.
• Do images have alt text? It helps people using a screen reader and tells Google what is in the image.

Checklist 4: structure, URLs and duplicate content

• Use short, readable URLs, such as /services/dormer-installation/ instead of /page?id=123.
• Give each page one clear H1 heading and use subheadings in a logical order.
• Give each page a unique page title and meta description. Write them for people: what will the visitor find on this page?
• Avoid duplicate content. Does the same page exist at several addresses, for example because of filters or parameters? Then use a canonical tag. It tells Google which version is the real one.
• Link internally between your pages. Important pages should be reachable within a few clicks from the homepage.
• Consider structured data: extra code that tells Google what something is, such as a business, a product or a frequently asked question.

Checklist 5: errors and redirects

• Look for 404 errors: pages that no longer exist. Search Console shows them. Send old addresses to the best new page with a 301 redirect. A 301 is a permanent redirect.
• Avoid redirect chains, where page A goes to B and B goes on to C. Point straight to the final destination.
• Check internal links that point to a 404 or a redirect, and update them.
• Watch out for server errors (5xx). They often point to hosting or code problems and need a developer.

Where does technical SEO often go wrong?

In practice we see the same problems again and again. The biggest pitfall is a website relaunch without redirects. Old pages disappear, new addresses have no history, and visitors from Google land on an error page. So before a relaunch, always make a list of old URLs and where they should go.

Other classics: a noindex that was left on after launch, a site that is slow because of heavy images, and a theme or plugin that loads lots of scripts nobody uses. On a WordPress site with many plugins, that adds up quickly. A custom site is often lighter, but someone still needs to keep an eye on the technical side.

How Violexa handles technical SEO

When we build a website, we include the technical basics from the start: fast pages, clean URLs, a sitemap, proper headings, redirects when relaunching, and Google Analytics. That comes as standard with a custom website or web application, from €1,799 excl. VAT (€2,177 incl. VAT) per project, including design, development, a design that works on every screen, CMS integration and training.

Already have a site and want someone to check and improve the technical side? That is possible through our online marketing, from €599 excl. VAT (€725 incl. VAT) per month, cancel monthly.

Want to know how your site is doing technically first? Request a free quickscan. In 30 minutes we go through your website, online or on site. Afterwards you get short written advice with a price estimate, with no obligation.

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