---
title: "What Are Core Web Vitals and PageSpeed?"
description: "Core Web Vitals are field metrics for loading, responsiveness, and visual stability: LCP, INP, and CLS. PageSpeed Insights combines field and lab diagnostics."
canonical: "https://gscpulse.behlul.com/glossary/core-web-vitals-pagespeed/"
language: "en"
updated: "2026-08-06"
robots: "noindex, follow"
---

[Home](/)›[Glossary](/glossary/)›What Are Core Web Vitals and PageSpeed?

GSC Pulse

# What Are Core Web Vitals and PageSpeed?

Core Web Vitals are field metrics for loading, responsiveness, and visual stability: LCP, INP, and CLS. PageSpeed Insights combines field and lab diagnostics.

## Why it matters

They help teams find user-experience problems that can affect usability and page experience.

## How to use it

Target LCP at or below 2.5 seconds, INP at or below 200 milliseconds, and CLS at or below 0.1 at the 75th percentile, while diagnosing field and lab data separately.

## Limits and interpretation

A perfect Lighthouse score is not the goal, and lab results do not replace real-user field data. Content usefulness and overall experience still matter.

## Common mistakes

Chasing a score without fixing the user journey; loading heavy third-party scripts; omitting image dimensions; confusing lab and field metrics.

## Questions people also ask

[Why are Lighthouse and CrUX different?](/faq/)[How can static sites improve LCP?](/faq/)[What causes layout shift?](/faq/)

## Where GSC Pulse fits

GSC Pulse uses this concept inside a decision workflow and links to the underlying evidence instead of presenting the term as a decorative metric.

[Primary documentation](https://web.dev/articles/vitals)Source

### Use the concept in a real portfolio review

Install GSC Pulse or continue with the related methodology and guides.

[Add to Chrome](https://chromewebstore.google.com/detail/gsc-pulse-%E2%80%93-google-search/namkhkodekmjikapbmbcpaahheokokhm) [Methodology](/methodology/)

**Related definitions**[Glossary](/glossary/)[FAQ](/faq/)[Related guide](/blog/search-console-portfolio-management/)