Core Web Vitals are Google’s core metrics for real user experience and they affect both rankings and conversion. For export businesses that depend on their own website for leads, speed is inquiry volume.
What are Core Web Vitals
Direct answer: Core Web Vitals consists of three metrics — LCP (loading), INP (interactivity) and CLS (visual stability), with thresholds of LCP < 2.5s, INP < 200ms and CLS < 0.1. Only when all three are green does it count as “good”.
It is not the same as an ordinary “how fast the page opens” measurement; it is an experience signal measured with real user data (CrUX). Google folded it into ranking factors from 2021 and it remains a hard threshold in technical SEO.
LCP: Largest Contentful Paint
Direct answer: LCP measures how long it takes the largest element in the viewport (usually the hero image or hero headline) to finish rendering, with a target of < 2.5s.
The most common LCP drag on export sites is uncompressed product images. How to fix it:
- Convert images to WebP/AVIF and preload the hero image (
<link rel="preload">). - Turn on a CDN and distribute static assets from nearby nodes.
- Server-side render the first-screen HTML so content does not depend on JS.
INP: Interaction to Next Paint
Direct answer: INP replaced FID from 2024; it measures how fast a page responds to clicks and input, with a target of < 200ms.
Filters, forms, language switchers and other interactions all trigger INP. Optimisation focuses on breaking up long tasks and deferring non-critical JS.
CLS: Cumulative Layout Shift
Direct answer: CLS measures unexpected movement of page elements, with a target of < 0.1. Reserving fixed dimensions for images, ads and embeds keeps it under control.
Common pitfalls on export websites
- Uploading product images as raw PNG originals (several MB each).
- No CDN means high latency for overseas buyers.
- Using a pure SPA with the first screen rendered by JS — slow for both crawlers and users.
⚠️ Note: the thresholds in this guide are based on Google’s public documentation; industry benchmarks shift over time, so treat live PageSpeed Insights / Search Console data as the final reference before launch.
| Metric | Good | Needs improvement | Poor |
|---|---|---|---|
| LCP | < 2.5s | 2.5–4.0s | > 4.0s |
| INP | < 200ms | 200–500ms | > 500ms |
| CLS | < 0.1 | 0.1–0.25 | > 0.25 |
FAQ
- What LCP counts as passing?
- LCP under 2.5s is good, 2.5–4.0s needs improvement and above 4.0s is poor. Export websites should prioritise bringing the hero image / hero section in under 2.5s.
- Which older metric did INP replace?
- From 2024 INP replaced FID as a Core Web Metric; it measures how quickly a page responds to user interaction, with a target under 200 ms.
- What slows export websites down the most?
- The most common culprits are uncompressed product images, no CDN and render-blocking JS. These three usually deliver the biggest speed gains.
- What is CLS and how do you control it?
- CLS measures unexpected movement of page elements, with a target under 0.1. Reserve fixed dimensions for images, ads and embeds and avoid injecting content above existing content.
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