- Core Web Vitals are a direct Google ranking factor since 2021
- LCP <2.5s, CLS <0.1, INP <200ms — targets for "good" status
- Most common cause of poor LCP: unoptimised images
- Check CWV in Search Console — real data from Chrome users
- Improving CWV directly affects conversion, not just rankings
What are Core Web Vitals
Core Web Vitals are three Google metrics measuring real user experience on your site. Since 2021 Google includes them in its ranking algorithm as an official signal. This means: a site with poor CWV can lose positions even with quality content.
LCP — Largest Contentful Paint
Measures loading time of the largest visible element on screen. Target: under 2.5 seconds.
Common causes of poor LCP:
- JPEG/PNG images without optimisation — switch to WebP
- Missing lazy-load — browser loads all images immediately
- Slow server (TTFB >600ms) — consider a CDN
- Blocking JavaScript — use defer/async for non-critical scripts
CLS — Cumulative Layout Shift
Measures layout instability: how much elements "jump" during loading. Target: under 0.1.
Most common causes: images without width/height attributes, dynamic content (banners, ads) inserted after page load, web fonts without font-display:swap.
INP — Interaction to Next Paint
Measures time from user interaction (click, tap) to interface update. Target: under 200ms. Replaced FID in March 2024 as a more accurate metric.
How to check Core Web Vitals
| Tool | Data type | Cost |
|---|---|---|
| Google Search Console | Field (real users) | Free |
| PageSpeed Insights | Field + lab | Free |
| Chrome DevTools (Lighthouse) | Lab | Free |
| WebPageTest | Lab + filmstrip | Free |
We'll audit your site and provide a fix plan within 48 hours.
How to fix — action plan
- Images — convert to WebP, add width/height attributes, implement lazy-load
- Fonts — font-display:swap, preload for critical fonts
- JavaScript — defer/async, code splitting, remove unused libraries
- Server — configure caching, CDN, Brotli/gzip compression
- Verify — recheck in Search Console after 2–4 weeks (data updates slowly)
