What Is Technical SEO and Why It Matters More Than You Think

When most people think about SEO, they think about keywords — writing content that includes the phrases people search for. That’s on-page SEO, and it matters. But there’s another layer that operates underneath the content — technical SEO — and for many websites, it’s the reason content efforts fail to produce rankings despite months of work.

Technical SEO is the practice of ensuring that search engines can find, crawl, understand, and index your website correctly. If the technical foundation is broken, even the best content won’t rank. Here’s what it covers and how to know if your site has a problem.

Crawlability — Can Google Find Your Pages?

Before Google can rank a page, it has to be able to reach and read it. ‘Crawlability’ refers to whether Google’s bots can access your pages. Common crawlability issues include: pages blocked by robots.txt (a file that tells search engines which pages to crawl or skip), noindex tags added accidentally to important pages, pages orphaned from the internal linking structure (no other page links to them), and JavaScript-rendered content that Google’s crawler can’t fully process.

Check: Go to Google Search Console → URL Inspection → enter any important page URL → see whether it’s indexed and if not, why.

Indexability — Are Your Pages in Google’s Database?

Crawlability is about access. Indexability is about whether Google chooses to store your pages in its index — the database it pulls search results from. Duplicate content, thin content, and canonical tag errors are the most common reasons pages are crawled but not indexed. Google won’t index multiple pages with nearly identical content — it picks one and ignores the rest.

Canonical tags tell Google which version of a URL is the ‘official’ one. Misconfigured canonicals are one of the most common technical errors on WordPress sites, particularly sites using WooCommerce, where product variations and filter parameters can generate hundreds of near-duplicate URLs.

Site Speed and Core Web Vitals

Page speed is a direct Google ranking factor via Core Web Vitals. The three metrics that matter: LCP (Largest Contentful Paint — how fast the main content loads), INP (Interaction to Next Paint — how quickly the page responds to user input), and CLS (Cumulative Layout Shift — whether elements jump around as the page loads). Google’s Search Console shows your Core Web Vitals status. A failing score means you’re being penalised in rankings relative to faster competitors.

This is one of the most commonly neglected technical issues — and one of the highest-impact to fix. Our WordPress maintenance plans include regular Core Web Vitals monitoring and optimisation.

Mobile-Friendliness

Google uses mobile-first indexing — your site is evaluated and ranked based on its mobile version, not desktop. If your site isn’t fully functional, fast, and easy to use on a phone, your rankings reflect that. Test your site with Google’s Mobile-Friendly Test tool. Issues to look for: text too small to read without zooming, touch targets too close together, content wider than the screen, and mobile page speed worse than desktop.

HTTPS and Security

HTTPS is a confirmed Google ranking signal and a user trust signal. Sites still running on HTTP are being flagged as ‘Not Secure’ by Chrome and other browsers. If your site doesn’t have a valid SSL certificate, fix this immediately — it’s a one-time setup that most hosts provide for free via Let’s Encrypt.

URL Structure

Clean, descriptive URLs help both users and search engines understand what a page is about before clicking. Compare: yoursite.com/p=1284 vs yoursite.com/wordpress-development-services — the second communicates the page’s topic clearly. URL structure decisions made at launch are expensive to change later (requiring 301 redirects at scale), so getting it right from the start is important. We covered best practices for URL slugs in our RankMath post — the same principles apply here.

XML Sitemap and Robots.txt

Your XML sitemap tells Google which pages exist on your site and when they were last updated. Your robots.txt file tells Google which pages to skip. Both need to be correctly configured. Common problems: the sitemap includes pages you don’t want indexed (admin pages, tag archives, filter variations), or robots.txt is blocking pages you do want indexed. In WordPress, RankMath or Yoast generates and submits your sitemap automatically — but the configuration still needs to be reviewed.

Schema Markup (Structured Data)

Schema markup is code added to your pages that tells Google explicitly what the content represents — a business, a product, a review, an FAQ, an event, a recipe. Correct schema markup can produce ‘rich results’ in Google — star ratings, FAQs, product prices, and other enhanced displays that increase click-through rates significantly. Organization schema, LocalBusiness schema, and FAQPage schema are the most valuable starting points for most business websites.

Internal Linking Architecture

How pages on your site link to each other affects both crawlability (Google discovers pages by following links) and authority distribution (link equity flows through internal links). Important pages should be linked from multiple places on the site. Navigation, footers, and in-content links all contribute. A page with no internal links pointing to it is functionally invisible to search engines.

How to Audit Your Technical SEO

A technical SEO audit uses tools to systematically identify issues. Google Search Console (free) covers indexing status, Core Web Vitals, and mobile usability. Screaming Frog (free up to 500 URLs) crawls your site and identifies broken links, missing meta tags, duplicate content, and redirect chains. PageSpeed Insights audits Core Web Vitals. For a comprehensive audit that covers all of the above and provides a prioritised fix list, our digital marketing team offers technical SEO audits as a standalone engagement.