Skip to content

What is the Difference Between LCP, INP, FID, and CLS?

Most people with websites know what the Google core web vitals are by this point. They were developed just a few years ago in 2021, when Google released their new way of ranking websites based on user experience. At the time, those core web vitals included LCP, FID, and CLS, but that changed a little in March 2024, when…
Reading Time: 5 minutes
Blog Post

Most people with websites know what the Google core web vitals are by this point. They were developed just a few years ago in 2021, when Google released their new way of ranking websites based on user experience. At the time, those core web vitals included LCP, FID, and CLS, but that changed a little in March 2024, when Google introduced the core vital INP.

So, what do all these acronyms mean? For those eager to appease Google and, in turn, run a successful website, understanding what these core web vitals are is crucial (of course, you can also use high-quality SEO services to manage the tricky parts for you).

Why Do Core Web Vitals Matter?

It’s all about improving user experience and boosting your Google ranking. If you’re a website owner, you want to appeal to both Google and any user who clicks on your site. As the name would suggest, core web vitals refer to the absolutes of website metrics – three main metrics of your website that give a particular score, painting a picture of how well the website runs for users. The better the score, the better your website runs, and everyone knows user experience matters most!

LCP, INP, and CLS (and, previously, FID) are the core web vital metrics, and each is essential to know about in its own right. A technical SEO audit can help cover these metrics, including the technical parts of making your website rank higher on search engines.

Itching to boost your ranking? You can learn more about on page SEO to find out how it might benefit your business.

LCP Meaning

Let’s discuss LCP first, which stands for Largest Contentful Paint. So, what is LCP? LCP is a core web vital that measures the biggest piece of visual content on the webpage – for example, that might mean a large image at the top of the page. This one’s all about speed, measuring how long it takes to visually appear on the screen. An LCP speed of 4.0 seconds or below is poor, between 2.5 and 4.0 seconds falls under ‘needs improvement’, and a speed of 2.5 seconds or faster is considered good. Naturally, to avoid an LCP issue, you’ll want to fall under the ‘good’ category.

Google Core Web Vitals, LCP (Largest Contentful Paint

CLS Meaning

CLS – which stands for Cumulative Layout Shift – is another metric measured by Google and part of the core Google web vitals. Unlike LCP, this one doesn’t focus so much on speed. Instead, it measures the visuals that move around on the page when a user is on there. The more visual movement, the more annoying it can be for the user, creating a poorer experience. The better

web pages have far more stability, and this will give you a better CLS score, which is anything above 0.1. Between 0.25 and 0.1 falls under ‘needs improvement’, and anything under 0.25 is ‘poor’.

Google Core Web Vitals, CLS (Cumulative Layout Shift)

If you’re interested, you can read more about our  SEO Consultancy Services.

FID Meaning (Outdated)

When the core web vitals were first introduced in 2021, they consisted of LCP, CLS, and FID, but FID has since been replaced with INP (which we will go into below). However, it’s still worth knowing what FID was and what it measured, as well as why it may have been replaced.

FID – which stands for First Input Delay – was a core ranking metric that measured the time between the user’s first interaction and the website’s initial response. The faster, the better. When measured, a good FID score was anything above 100ms, and a poor FID score was under 300ms.

Google Core Web Vitals, FID (First Input Delay)

INP Meaning (New as of 2024)

Google Web Vitals introduced INP as a replacement for FID in March 2024. INP stands for Interaction to Next Paint, a metric that assesses how quickly a website responds to the user’s interactions. Instead of focusing on the single metric of the first user interaction – which is what FID measures – it’s more of an overall measurement that takes all the user interactions into account while they are on a page.

Google Search Console, Screenshot of INP report March 2024

A diagram of the life of an interaction:

A diagram depicting INP interaction

Google scores the INP by the longest metric taken. A poor score is over 500ms, a score that needs improvement is between 200-500ms, and a good score is below 200ms.

Google Core Web Vitals, INP, Interaction to Next Paint

Get an SEO audit here and see how your website is doing, so you have a better picture of your website’s performance and what you can do to improve it.

How to Optimise Google Core Vitals

The first step to optimizing web core vitals is to understand the core vitals definition and know how to measure them. The good news is there are plenty of excellent tools to measure your core web vitals, including Lighthouse, Google Search Console, and PageSpeed Insights. Once you know your metrics, you’ll be able to see where your website may be failing and make the adjustments as necessary. A good SEO management strategy should encompass this, helping you tackle the core web vitals and ensure your website consistently produces good scores.

Google Search Console data results

PageSpeed Insights report of Click Intelligence performance

Boost Your Ranking with Our SEO Services

It can be challenging to navigate the ever-evolving factors that affect your website’s performance and overall ranking. It can feel like a dark art that you’ll just never get the hang of. That’s why so many of the best-performing websites use SEO services, taking advantage of the expertise out there rather than trying to go it alone. At Click Intelligence, we offer a wide range of SEO services, including international SEO, enterprise SEO, and white label SEO, to help you tackle all your search engine needs. We understand that a small business’s SEO strategy should be different from an enterprise, and we tailor our services to meet your specific needs.

Hopefully, we have given you a simple core web vitals definition and made the metrics like Google CLS and INP much clearer. If you have any questions about Google core web vitals or search engine optimisation as a whole, get in touch with the Click Intelligence team today!

View all Downloads

Downloads

The cover image of our e-book titled 'Content Marketing How-To Guide', portraying an individual typing on a laptop.

Content Marketing – How-to Guide

What is Content Marketing? Download Our How-To Guide Today!

Download
Beginner's Guide to Rich Snippets?

Beginner’s Guide to Rich Snippets

Find out the secret code of how to get a rich snippet in Google.

Download

Link Building Vs Managed SEO: What’s Right For Your Business?

Link Building or Managed SEO which is right for me?

Download
View the Blog

You may also be interested in...

Brand Mentions Are Pulling More Weight in SEO Than You Think

Remember when your search authority boiled down to how many backlinks you had? The more…

Combining GEO and PPC to Maximise SEO Visibility

Gone are the days when SEO visibility was all about rankings. AI search has changed…

How to Rank in AI Search as a Small Business

Just when you think you’ve got SEO for small businesses figured out, along comes the…

How Brands Convert Without Clicks in Zero-Click SEO

Not too long ago, success in search was simple. Get the click, win the customer…

Google Core Update March 2026: Next Steps

Now the dust has settled on the March 2026 core update, and if you’ve been…

Why Personas Are Essential for Modern SEO and AI-Driven Search

For years, SEO has been driven by a relatively simple formula: identify the right keywords,…

How AI Search Is Presenting Your Brand (And How Click Insights Helps You Track It)

The introduction of the internet forever changed how brands experienced visibility, and, with its updates…

How Content Hubs and Entity Clusters Drive AI SEO Performance

Search is getting smarter by the day, and the way we create content needs to…

View all Guides

Online Guides

The Ultimate Digital PR Strategy Guide
View guide
The Ultimate SEO & AI Search Strategy Guide for Sports Betting
View guide
The Ultimate SEO & AI Search Strategy Guide for iGaming
View guide
Best PR Link Building Agencies
View guide
Best UK PR Link Building Agencies
View guide
Best UK Brand Mentions Agencies
View guide
The Ultimate SEO & AI Search Strategy Guide for Car Dealers
View guide
Brand Mentions SEO & AI Search Strategy Guide
View guide
Back To Top