Google has been clear for years: a fast, stable page is a ranking signal. But most "speed up your site" advice is noise. Here are the five fixes that actually move the needle on LCP, INP and CLS — the three Core Web Vitals that matter in 2026.
First, measure the right thing
There are two kinds of data, and they are not the same:
- Lab data (Lighthouse in your browser) is a controlled test on a simulated device.
- Field data (Chrome UX Report) is what real visitors on real phones actually experienced.
Google ranks on field data. Optimise for the numbers real users see, not the pretty score on your fast laptop. If the two disagree, the field wins.
1. Fix your Largest Contentful Paint element
LCP measures how long until the biggest thing on screen — usually the hero image or headline — is painted. The two most common killers:
- A hero image that is huge and loads late. Serve it in a modern format, size it for the actual viewport, and mark it as high priority so the browser fetches it first.
- Render-blocking fonts. Self-host your fonts and let text show immediately with a fallback while the brand font loads.
Aim for LCP under 2.5 seconds on mobile.
2. Kill layout shift before it happens
Cumulative Layout Shift is the jump you feel when an image or ad pops in and shoves the text you were reading. It is almost always preventable:
- Always set explicit width and height (or an aspect ratio) on images and video.
- Reserve space for anything that loads late — banners, embeds, cookie bars.
- Never inject content above what the user is already looking at.
Target a CLS below 0.1. This one is cheap to fix and users notice instantly.
3. Trim your JavaScript
Interaction to Next Paint (INP) replaced the old FID metric and it is stricter. It measures how quickly the page responds when someone taps or clicks. Heavy JavaScript is the usual culprit — the main thread is busy, so the tap feels dead for a moment.
- Ship less script. Every library has a weight; question each one.
- Load non-critical code only when it is needed, not on first paint.
- Break long tasks into smaller chunks so the browser can respond between them.
Target INP under 200 milliseconds.
4. Serve from the edge
Where your server lives matters. A visitor in Karachi hitting a server in Virginia pays for every round trip. A CDN keeps a copy of your site close to the user, so the first byte arrives fast. For most marketing sites, static pages served from the edge are the single biggest win available — and they cost less to run, not more.
5. Respect the mid-range phone
The device that matters is not the newest flagship. It is a two-year-old Android on a patchy connection — which is what most of your audience is actually holding. If your site is smooth there, it is smooth everywhere. Test on a real, modest phone before you call it done.
The honest summary
You do not need a hundred micro-optimisations. You need: a fast hero, zero layout shift, lean JavaScript, edge delivery, and a real mobile test. Get those five right and your field scores — and your rankings — will follow.
Want to know exactly where your site stands? Our free AI audit measures these signals on your real page and tells you what to fix first.