Website Speed and Core Web Vitals: What Actually Costs You Enquiries
Speed scores are a means, not a goal. What matters is whether a visitor on a mid-range phone can see your offer and tap the button before they give up.
By Ads Ninza · Published 16 September 2026 · 6 min read
The three Core Web Vitals, in plain terms
LCP, Largest Contentful Paint. How long until the main content, usually the hero image or headline, appears. Google treats 2.5 seconds or less as good.
INP, Interaction to Next Paint. How quickly the page responds when someone taps or clicks. It replaced First Input Delay in 2024. 200 milliseconds or less is good.
CLS, Cumulative Layout Shift. How much the page jumps around while loading. 0.1 or less is good. High CLS is what makes people tap the wrong button.
These are measured on real visitors through the Chrome User Experience Report, shown in Search Console and PageSpeed Insights. The lab score in PageSpeed Insights is a simulation. The field data is what your visitors actually experienced.
Why speed costs enquiries
Paid traffic is the most sensitive. Someone who taps an ad and waits several seconds for a blank page often goes back and taps the next ad. You have paid for the click and lost the visitor.
Mobile is where it hurts most. Most visitors to most business sites arrive on a phone, often a mid-range Android on a mobile connection, not the latest iPhone on office Wi-Fi. A page that feels fine on your laptop can take much longer for them.
Speed also affects Google Ads through landing page experience, which feeds Quality Score and your cost per click. It is a factor in organic ranking too, though content and relevance matter more.
The fixes that matter most, in order
1. Images. The most common problem. Serve modern formats such as WebP or AVIF, at the size they are displayed, with width and height set so the layout does not jump. Load the hero image early and lazy-load everything below the fold.
2. Fonts. Load only the weights you use, preconnect to the font host or self-host, and use font-display so text appears immediately.
3. Third-party scripts. Chat widgets, heatmaps, multiple tracking pixels, review widgets and social embeds add up. Remove what you do not use. Delay the rest until after the page is interactive or the visitor interacts. This is usually the main cause of poor INP.
4. Heavy themes and page builders. Many templates load large amounts of CSS and JavaScript for features you never use. Sometimes a lighter theme is the only real fix.
5. Hosting and caching. A CDN, server caching and compression help, especially for visitors far from your server.
Our own site went from mid-80s to 100 on mobile PageSpeed with exactly these steps: images reduced from about 46 MB to under 3 MB, critical CSS inlined, fonts loaded without blocking, and analytics deferred until interaction.
How to test properly
Run PageSpeed Insights on your key landing pages, not just the home page. Look at field data first, if available, then the lab diagnostics.
Then open the pages on a mid-range Android phone on mobile data. Time how long until you can read the offer and tap the main button. Try the form. This simple test catches problems scores miss, such as a cookie banner covering the button or a chat widget opening over the form.
Check Search Console's Core Web Vitals report monthly to see how groups of pages perform for real visitors.
We build landing pages to these standards as part of Revenue Landing Systems, and our landing page conversion guide covers what goes on the page.
Speed across markets
In India, a large share of traffic comes from mid-range Android devices on mobile networks, and page weight matters more than in most markets. In the UAE, connection speeds are generally high, but visitors are demanding and the same third-party script problems apply.
For businesses serving the USA, UK and Canada from a server in another region, a CDN makes a noticeable difference. Accessibility and speed often improve together, and in the USA accessibility carries legal weight for business websites.
Frequently asked questions
What are Core Web Vitals?
Three measures Google uses to assess page experience: Largest Contentful Paint for loading, Interaction to Next Paint for responsiveness, and Cumulative Layout Shift for visual stability. Good thresholds are 2.5 seconds, 200 milliseconds and 0.1 respectively.
Does website speed affect conversions?
Yes, especially for paid traffic on mobile. Visitors who wait too long for a page often leave before seeing the offer, and you have already paid for the click. Faster pages usually convert better, though content and offer matter more.
Does page speed affect Google rankings?
It is a ranking factor, but a smaller one than content relevance and quality. It also affects Google Ads through landing page experience, which influences Quality Score and cost per click.
What is a good PageSpeed Insights score?
Scores of 90 and above are considered good. More important than the lab score is field data from real visitors, which shows whether your pages pass Core Web Vitals. A perfect score is not necessary if real visitors have a fast experience.
What is INP and how do I improve it?
Interaction to Next Paint measures how fast a page responds to taps and clicks. Poor INP is usually caused by heavy JavaScript, particularly third-party scripts such as chat widgets, tracking tags and page builder code. Remove or delay non-essential scripts.
Why is my website slow on mobile but fine on desktop?
Mobile devices have less processing power and often slower connections. Large images, heavy JavaScript and many third-party scripts that a laptop handles easily can make a mid-range phone struggle. Test on a real phone on mobile data.
Do tracking pixels slow down my website?
They can, especially when several are loaded at once. Defer them until after the page loads or the visitor interacts, and consider server-side tracking to move work off the browser. This keeps tracking accurate without slowing the page.
Is WordPress slow?
WordPress itself can be fast. Heavy themes, page builders and many plugins make it slow. A light theme, few plugins, image optimisation and caching usually solve most WordPress speed problems.
How often should I check website speed?
Monthly for key pages, and after any change such as a new plugin, widget, theme update or tracking tag. Speed often degrades gradually as small additions pile up.
How do we start with Ads Ninza?
Apply through the form on this page. On a paid discovery call, INR 499 in India and $9 elsewhere, we test your key pages on mobile with you and show you what is costing enquiries. Landing page and website work is quoted after that call.