6 Best Practices to Improve Website Speed & Core Web Vitals

Improving your site’s speed and Core Web Vitals is achievable through a series of best practices. Many are straightforward, while others might require some development work or professional help. The payoff, however, is worth it: a faster, smoother site that pleases both users and search engines. Here are key strategies to boost performance:

1. Optimise Images and Media

Images are often the largest assets on a webpage, so optimising them can yield huge speed gains. Ensure you’re using the appropriate formats and sizes for each image. For example, serve modern formats like WebP or AVIF which provide better compression than old JPEG/PNG formats. Compress images to reduce file size (without noticeable quality loss) – tools or plugins can automate this. For SMEs, this might mean using a WordPress plugin (like Smush or ShortPixel) or an online compressor before uploading images. For agencies, establish an image optimisation workflow for all client sites (you could even enforce image size limits in a CMS). Also consider responsive images (the srcset attribute) so browsers only download the resolution needed for the user’s device.

Don’t forget other media: videos should be compressed and, if they autoplay in the background, consider removing or replacing with a static image to improve LCP. Also implement lazy loading for images and iframes – this defers loading images that are off-screen until the user scrolls to them, greatly reducing initial load times. In fact, lazy-loading images can improve both LCP and INP (by reducing main-thread work early on).

Insight: Nearly 39% of visitors will abandon a website if images take too long to loadsitebuilderreport.com. Optimising media not only improves metrics, it directly keeps impatient users engaged.

2. Use Fast, Reliable Hosting (and Consider a CDN)

Your web host plays a foundational role in site speed. An entry-level shared hosting plan might be cheap, but if the server is slow or overloaded, your site will suffer (especially in Time to First Byte, an indicator of server responsiveness). Upgrade your hosting to match your needs: for SMEs, that might mean moving from shared hosting to a managed hosting service or a VPS (virtual private server) with better performance. For high-traffic or international audiences, a dedicated server or cloud solution might be warranted. HostLogic.ie (our sister company), for instance, focuses on high-performance hosting and maintenance – leveraging such specialised hosting can give you a speed edge through optimised server configuration and caching.

Additionally, implement a Content Delivery Network (CDN). A CDN caches your site’s static content (images, CSS, JS, etc.) on servers around the globe, so when a user in Dublin or New York visits your site, they fetch files from the nearest location instead of, say, your origin server in London. This drastically cuts down network latency and improves load times for distant users. Cloudflare, Amazon CloudFront, Fastly, and others are popular CDN options (Cloudflare even has a free plan that covers basic CDN and some optimisation). Many hosting providers include a CDN or have easy integration.

For agencies managing multiple client sites, standardising on a quality hosting environment or recommending a preferred host can save a lot of headaches. Some agencies even offer white-label hosting to clients (reselling managed hosting) to ensure all sites they build run on optimised infrastructure. This also creates an additional revenue stream and control over performance. At minimum, advise your clients not to skimp on hosting – it’s truly the foundation of a fast website.

3. Minimise and Optimise Your Code

Every additional script or stylesheet a page loads is another task for the browser. By reducing the amount of code and resources, you speed up loading and interaction. Key tactics include:

• Minification: Compress your HTML, CSS, and JavaScript files by removing whitespace, comments, and unnecessary characters. Minified files are smaller and thus faster to download. Most build processes or plugins (like WP Rocket, or using a tool like Terser for JS) can do this automatically.

• Combine files (to an extent): In the past, combining CSS/JS files was important to reduce HTTP requests. With HTTP/2 and HTTP/3, parallel downloads are better, so this is less critical now – but still avoid an excessive number of separate files. Grouping CSS into a couple of files and JS into a few bundles can help the browser manage them efficiently.

• Defer non-critical scripts: Use the defer or async attribute for JavaScript files, especially third-party scripts, so they don’t block the initial rendering of the page. This improves your First Contentful Paint and LCP by not letting scripts hold up the browser’s parsing of HTML.

• Remove unused code: Over time, websites collect bloat – maybe unused CSS from older designs, or JavaScript for features you removed. Audit your code and eliminate what’s not needed. Tools like Chrome DevTools can highlight unused CSS/JS in a page. Less code = less to download and execute.

• Choose plugins carefully (for CMS users): If you’re on WordPress, Joomla, etc., be mindful that each plugin may add its own scripts/styles. Deactivate and delete plugins that aren’t crucial. Look for lightweight plugin alternatives or those that offer modular loading (only loading on specific pages where needed).

By streamlining code, you also improve INP because the browser has fewer tasks hogging the main thread. Long JavaScript tasks are a common cause of poor interactivity (they can block user input processing). So trimming and optimising code not only helps loading time but ensures the site stays responsive to clicks and taps. Agencies: implement performance budgets during development (e.g., target < X MB of resources, or < N ms of script execution) to keep sites lean. This way, performance is baked in from the start, not an afterthought.

4. Enable Caching (Browser & Server-Side)

Caching is one of the most powerful ways to speed up repeat visits and reduce server load. There are a few layers to consider:

• Browser caching: Ensure your server sends proper cache-control headers for static resources (images, CSS, JS, etc.), so browsers store those files and don’t re-download them on every visit. For instance, your logo image or site CSS can be cached for days or weeks, making subsequent page loads much faster for the user. This is usually configured in your server or via a CDN. A user’s first visit might be 3 seconds, but if caching is enabled, the next visit could load almost instantly as assets are reused from cache.

• Server-side caching: If your site has dynamically generated pages (common with WordPress, Drupal, etc.), use a caching mechanism to serve static HTML versions of pages to users instead of hitting the database each time. WordPress plugins like WP Super Cache or W3 Total Cache do this, and many hosts have built-in server caching. Cached pages greatly improve Time to First Byte and initial render, contributing to a better LCP. For agencies building sites, make sure to configure page caching on production – it’s an easy win for performance.

• Object caching & others: For web applications, techniques like object caching (storing database query results in memory), OPcode caching (for PHP sites, to cache compiled PHP code), and so on can further boost speed. These are a bit more technical, but any good host or developer will handle it. The result is less processing per request, which means faster responses.

In summary, caching lets your site “remember” the work it has done before, so it can serve future users faster. It’s like meal-prepping for your server: instead of cooking from scratch for each visitor, you have pre-made content ready to go. Just be mindful of purging the cache when you update content, so visitors see fresh info when they should.

5. Prioritise Critical Content & Improve Perceived Speed

Perception is reality. Sometimes you can’t make everything load in 1 second, but you can ensure that the important parts load first and that the user feels the site is fast. Techniques include:

• Critical CSS: Inline the CSS needed for above-the-fold content directly in the page’s <head> (or use server push for it). This way the browser can render the top portion of the page immediately, without waiting to download the entire CSS file. The rest of your CSS can be loaded asynchronously. This improves Largest Contentful Paint, since your main banner/text can style and display faster.

• Lazy-load below-the-fold content: Not just images – you can defer loading heavy sections or scripts until the user scrolls down. For example, if you have a video embed or a large map further down the page, using lazy loading or placeholder content can prevent it from slowing down the initial load.

• Prefetching & Preconnecting: You can hint the browser to prefetch resources or DNS connections that the user is likely to need next. For example, if the next page in a funnel is likely to be visited, prefetch its key assets. This can make navigation feel instant. Similarly, use dns-prefetch or preconnect for third-party domains (like your analytics script or a fonts provider) to reduce latency in establishing those connections.

• Avoid render-blocking resources: Ensure that any external fonts or scripts don’t block the page from showing content. Use font-display: swap for web fonts (so text is shown in a system font until the custom font loads, preventing a blank text layout). And put non-essential scripts at the bottom of the page or load them asynchronously.

These optimisations improve what’s often called perceived performance – the user sees a functional page quickly, even if some elements are still loading in the background. The quicker a user sees useful content or can interact (click, scroll), the better their experience, and the more likely they are to stay engaged. For SMEs, implementing just a couple of these (like enabling lazy loading which is often one setting or plugin) can make a notable difference. Agencies should make these techniques part of their standard development checklist to deliver sites that feel snappy.

6. Test, Iterate, and Continuously Improve

Website optimisation isn’t a one-and-done task. It requires a mindset of continuous improvement. After implementing changes, test your site again with the tools mentioned earlier. Did the metrics improve? Sometimes you might fix one bottleneck only to find the next one. For instance, you compress images and see LCP improve, but now your largest element is a slow-loading web font – so maybe you tackle that next. Treat it like tuning a race car: shave off milliseconds here and there.

For agencies, continuous monitoring and optimisation can even be framed as a service – e.g., quarterly performance tune-ups or ongoing optimisation retainers. With Google updating their algorithms and users shifting behaviors (e.g. more mobile usage every year), it pays to keep websites in peak shape. Also, watch for new Core Web Vitals updates. Google has hinted that additional metrics could be introduced as technology evolves. (For example, they introduced INP; in the future, maybe smoothness or other UX aspects could get metrics.) Staying informed via official Google Search Central updatesblog.cloudflare.com or web.dev articles will help you proactively adapt.

And of course, listen to your analytics: high bounce rate on a particular page? Maybe there’s a performance issue there. Low mobile conversion rate? Perhaps the mobile site is sluggish compared to desktop. Use data to guide your efforts.

One more thing: consider a professional audit if you’re not sure where to start or you’ve done the basics and still see poor scores. A detailed Website Performance & SEO Audit (like the one we offer) can uncover hidden issues – from misbehaving third-party scripts to server misconfigurations – and provide a clear action plan. Sometimes, an expert eye catches things others miss.