Why website speed is more than a technical detail
We can’t wait. It’s not that we think less of people—it’s just how we are made. These days, we need things right now. Data from Google shows that if a page takes 3 seconds instead of 1 to load, 32% more people will leave right away. If it hits 5 seconds, nearly all (90%) will leave.
From a mind view, this rush comes from too much to think about. Each tick of the clock makes waiting harder. It messes with the brain’s feel-good cycle, making us mad. We’ve been trained by fast sites like Instagram and Amazon to want things at once. When a site is slow, we think, without meaning to, that it just isn’t good, even if it’s a top brand.
This is key since most people don’t come back after a bad time. A study by Akamai shows that if a site takes two more seconds to load, the chance that someone leaves jumps by more than 100%. It’s not only about missing one visit—it’s about missing out on a future buyer.
Speed as a trust signal: What bounce rate really tells us
Bounce rate is not just a stat in Google Analytics—it shows how folk act. When a user leaves fast, it could mean they found the site slow, the content off-topic, or they hit problems they didn’t want to deal with. Often, speed kills, most on phones.
High bounce rates harm how folks see your brand. A slow site suggests old tech, bad UX, or no care. All these break user trust. And when trust is down, making sales is super hard.
Speed, then, is not just skill—it shows how good you are. Quick websites seem more sure, more able, and more in step with what users want. At Dool, we’ve seen that bounce rate often ties with how sites perform, like how long they take to load, how fast the first byte comes, and how long they block.
When we talk of “making speed better”, we mean building trust for many, big.
Background on client challenges and KPIs
In the second part of 2024, we took on a mid-sized e-commerce store that sells stuff for homes. The site saw lots of visitors from both free and paid ads, but it wasn’t doing well. The site’s bounce rate was a high 74%, and less than 1% of visitors were buying. The team thought the problem was with the user experience, but first tests showed a bigger issue: the site was too slow on important pages.
Mobile users felt this the most—their load time was about 5.6 seconds, way over the good limit of 2.5 seconds. Google PageSpeed Insights showed bad server speeds, big images that weren’t cut down, and stuff that stopped the site from showing right away. What happened? People came, waited too long, and left without looking at the stuff to buy.
The task was plain: cut down on quick exits and keep more users, all without a total site redo. Our key goals were to cut quick exits by 40% at least, make the site load twice as fast, and really push up the number of checkouts and form fills.
Measuring the impact of speed: Pre- and Post-Optimisation Metrics
Over a six-week period, we implemented five core speed optimisations (detailed in the following sections). The transformation was not subtle.
- Bounce rate dropped from 74% to 28.3%—a 62% reduction
- Average load time decreased from 5.6 seconds to 1.8 seconds
- Mobile conversion rate increased by 19%
- Pages per session rose from 1.3 to 2.7, indicating deeper user engagement
These numbers were not just ideas—they got tracked with GA4, Hotjar, and Lighthouse checks. The faster site made people stay, look around, and buy more.
In simple words to the client, it was: “The site now truly values our customers’ time.”
1. Choosing the right hosting for speed and scalability
Our main job was to fix how fast the server replies. The client’s site was on a slow, cheap plan with a lot of wait time and not much data room. Often, pages took more than a second to start showing—before we could even see any stuff. This wait, called Time to First Byte (TTFB), is a key but often missed speed mark.
We moved the site to a fast, cloud-based Private Server with extra cache layers and fast drives (SSDs). This change cut crowding and made sure each visit had enough server help, even when lots of people came at once. Big point: it let us use new HTTP/2 rules and edge caching—sending files quicker from data centers near the user.
This wasn’t just a technical upgrade. For users, it meant the site felt instant. They clicked, and content responded.
Real-world results: Time-to-first-byte improvements
Before moving, the TTFB was at 920ms. After, it fell to 180ms. That’s 80% better, making pages start to load faster. This change was big, even if users didn’t know why.
A study in 2017 by Akamai said if TTFB is under 200ms, it cuts page load time by 0.5–1.0 seconds—big news for keeping people on the site. In this story, the mobile bounce rate went down by 23% in just two weeks after moving.
By fixing the unseen part first — how the server works — we made a good base for other big fixes to work well.
2. The role of visual assets in page load delays
The next big halt was image size. Product pages had a lot of big .PNG photos, some more than 2MB. They looked good but made loading slow, really on 4G phones. Users had to load whole pages to just move down.
This is a usual give and take in web making: picture look or speed. But now with new tools, it doesn’t have to be a loss.
We checked each picture on the site and swapped all still .PNG and .JPG files for smaller WebP types—cutting sizes up to 75% with no clear drop in how good they looked. For moving stuff, we put in a smart load that picks the right size for phones, using the srcset thing. This way, phone users get just the right sizes.
Tools, formats, and before-after performance benchmarks
To make the job of squashing image sizes easy and keep the look sharp, we used tools like ImageOptim, TinyPNG (through API), and Cloudinary for quick delivery. WebP turned into our go-to option because it shrinks files well and Google says it’s good for fast web speeds.
The change was quick:
- Total page size fell from 5.2MB to 1.8MB
- Page Load Time (on 3G) cut down by 1.4 seconds
- Largest Contentful Paint (LCP), a main Web Vitals score, got better by 38%
No one said a bad word about the picture look—none could see any bad things. The site started to feel more clean, quick, and sharp. And bounce rates? They went down 15% more in the two weeks after we set it up.
Making pictures better isn’t about giving up things—it’s about making it easy for users to see what they want to see.
3. Streamlining code to improve render speed
Today’s sites often rely on a mix of JavaScript and CSS to manage things like animations and how fonts look. But each file adds a new HTTP request and—if not made lean—brings extra bulk that slows the page’s load time. Our client’s first setup had over 40 different JavaScript files on just the homepage, many not used or loaded all at once.
We ran a full check using Chrome DevTools and Lighthouse to spot scripts and CSS rules that slowed things down. The fix wasn’t drastic—it was detailed. We made all CSS and JavaScript files smaller with tools like UglifyJS and cssnano. This cut out space, comments, and extra code. We put off less important code and set up third-party tools, like chat plugins and data trackers, to load one by one.
The main thing was focusing on what was key for the first view—what the user sees right away in that first second.
Effects on mobile vs desktop bounce rates
Once these changes were made, the way a page is made got a lot faster. Desktop load time got better by 900ms, and phones saw an even bigger drop—almost 1.6 seconds faster on average.
More so, users began to use the site sooner. Time to Interactive (TTI), a way to see when a page can be used, got 47% better. This is key for old phones where JavaScript is slow.
Phone bounce rates, which were the worst, went down by 14%, making the total leave rate closer to what is normal. What people often miss is that many leave not because they don’t want to stay, but because they can’t yet—since the page is still loading or not ready.
4. Delaying non-critical resources to boost perceived speed
One small but strong shift we made was to bring in lazy loading. This method lets images and videos wait to load until they show up on the screen. In easy words: stuff does not load until it is needed. And this is big for how fast things seem.
The product pages of the client had a lot of long text and many big, clear images lined up one on top of the other. Users had to wait a long time for each image to load, even if they only looked at the first few. With lazy loading, the web browser only loads what you can see right away. This cut down a lot on the first size and speed of the page.
We used built-in HTML lazy load (loading=”lazy”) for still images and videos. We also used IntersectionObserver for more complex stuff. This made sure it worked well on new web browsers and kept it simple.
Engagement metrics after deployment
After we rolled out the new feature, we saw a cool change. While people stayed on the site a bit longer, they scrolled 38% more. This shows they were looking at more stuff since they did not have to wait at the start. Also, 6% fewer people left the site fast, mainly on blog and product pages.
What lazy loading really helps with is making the site seem fast—users think it’s quicker because they see things right away. From a user thinking point of view, this quick action keeps them going and cuts down on mental hang-ups. It makes the brain stay in “active mode” instead of “wait mode”.
5. Switching to a lightweight CMS and CDN combo
Even with past fixes, a big block stayed: the CMS. The client was using a WordPress setup full of plugins, with a drag-and-drop builder that was easy to use, but made too many DOM nodes and needless in-line styles. Each page opened with over 1,000 parts, many not helping the user, but making load times long.
This is a usual problem—systems that offer more ways to use them often slow them down. Every added plugin, widget, or form grows the load. The more stuff in the back, the slower the front runs—this is worse when themes are badly made or can’t work well on phones.
To fix this, we moved the client to a simple CMS (Strapi) tied to a JAMstack setup using Gatsby. This split the content control from the display part, letting us make static HTML pages ahead of time that load very fast. With a worldwide Content Delivery Network (CDN), we made sure the site loaded fast from the closest spot, no matter where the user was.
Leveraging CDNs for global load efficiency
Content Delivery Networks put your site’s data in many places around the world at once. This cuts down lag and makes sure the site loads the same way everywhere. We teamed up with Cloudflare to store HTML, CSS, JS, and images out at the edge. What was the outcome? Fast loading speeds all over.
Before we did this, it took about 2.8 seconds for the site to load in the UK; in Spain and LATAM, it could take more than 4.6 seconds. After we set up the CDN, loading times in both areas got down to less than 1.5 seconds.
From a behavioural standpoint, this had a ripple effect:
- Bounce rate dropped a further 8.5%
- Average session duration increased by 31%
- Pages per session rose above 3.2, suggesting a more confident and exploratory user journey
Bounce rate vs conversion rate: The link in numbers
After all five optimisations were implemented, the results were not only measurable—they were transformative.
- Initial bounce rate: 74.2%
- Post-optimisation bounce rate: 28.3%
- Net reduction: 62%
- Mobile load time: from 5.6s to 1.8s
- Desktop load time: from 3.7s to 1.2s
- Checkout conversions: up 22%
- Lead form submissions: up 31%
- Return visitor rate: increased by 19%
The link between bounce rate and sales was clear. As blocks went down, so did user stops. People not just stayed more—they did more. Views of items per visit went up, left carts fell by 11%, and more users got to the checkout.
In their minds, users weren’t held back at the start. They had a clear way to look, choose, and buy.
ROI breakdown: From speed tweaks to lead generation
What grabs your eye most is the money made back. The full cost to set it up—including better hosting, hours spent building, and new tools—was under €4,000 for six weeks. The money coming in after grew a lot, all thanks to more people buying and better SEO scores (all from improved Core Web Vitals), and it went past that amount in just three months.
Also, the site saw a 26% rise in free traffic, thanks to faster load times and less people leaving quickly, which Google likes more. This boost in free visits made the money made back even higher, cutting down on the need to pay for ads and making the cost to get new people lower across all ways of reaching them.
Speed optimisation as an ongoing process
If we learned one thing from this case, it’s that web speed is not just a one-time job—it’s ongoing. Web tools get updates. Tech tools change. What users want goes up. What felt fast now may seem slow soon. The wins from these five changes didn’t just come from quick fixes, but from keeping a close eye on speed at every level—from the server to code to pictures.
It’s key to think past just starting and then stopping. Speed needs to be watched, checked, and fine-tuned all the time. At Dool, we’ve made performance checks a regular part of our clients’ monthly plans.
Integrating speed audits into digital strategy
Too often, making a site fast is seen as just a job for the people who build sites. Yet, every marketer should use it too. A quick site is not just about a good time for users—it also helps with SEO, cuts costs, and ups the value of each customer over time.
Every brand wants faster load times and lower bounce rates—but not every team has the time or technical depth to make it happen. If you’re ready to turn user impatience into engagement, let’s make your website work smarter and faster.
FAQs
How does website speed directly affect bounce rate?
Website speed impacts bounce rate by influencing how quickly a user can interact with your content. When a page takes too long to load (typically more than three seconds), users are more likely to abandon the session before engaging—especially on mobile devices. Google reports that each additional second of load time increases the probability of bounce by up to 32%.
What’s the ideal page load time for reducing bounce rates?
The benchmark for optimal performance is under 2.5 seconds for mobile and under 2 seconds for desktop. Achieving these speeds significantly reduces bounce rate and improves overall engagement. Sites that load in under 2 seconds tend to have bounce rates below 40%, compared to over 70% for those above 5 seconds.
Which tools are best for measuring website speed?
We recommend using a combination of:
- Google PageSpeed Insights for detailed Core Web Vitals
- Lighthouse for performance audits and improvement suggestions
- GTmetrix for load visualisation and historical tracking
- WebPageTest for real-world performance from different locations
Each tool provides unique insights that help diagnose and prioritise performance bottlenecks.
Can speed improvements really affect conversion rates?
Yes, absolutely. Numerous studies confirm that faster websites convert better. For example, Deloitte (2020) found that reducing mobile load time by just 0.1 seconds increased conversion rates by 8.4% for retail and 10.1% for travel. Our own client case saw a 22% increase in checkouts post-optimisation.
What’s the difference between TTFB, FCP, and LCP?
- TTFB (Time to First Byte): How fast your server starts to respond
- FCP (First Contentful Paint): When the first visual content appears
- LCP (Largest Contentful Paint): When the largest element on the page becomes visible
All three are critical to perceived speed and user satisfaction. Reducing each of them contributes directly to bounce rate reduction and higher engagement.
