Performance is a key aspect of the user experience. How fast pages load and how quickly they respond to user input can have a significant impact on how users perceive your site, and can make the difference between whether users stay on your website or abandon it. On this page, you'll find a wealth of information on various web performance topics that will help you make your website fast—and keep it fast.

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New to performance? We've got you covered with a comprehensive course to help you get started.
Get up to speed on the three Core Web Vitals metrics, how they work, and why they're important for good user experiences.
Once you've learned about Core Web Vitals metrics, these guides can help you to understand how best to optimize them.
Go even deeper into Core Web Vitals with a collection of guides that explore the metrics in more detail.
Discover new features for improving performance that are now Baseline Newly available.
Read about how companies improved their Core Web Vitals and saw an increase in their business metrics as a result.
Learn how you can use Chrome DevTools to debug performance issues on your website.
COURSE

Web performance is a complex and multi-faceted subject matter area—but it's not impossible to learn! If you're new to performance, our course will help you to hit the ground running by first introducing you to performance basis, allowing you to work your way through more advanced topics. Once you've completed the course, you'll be able to apply what you've learned in no time!

Learn Performance!

The Core Web Vitals metrics are a set of three metrics focused on the user experience. They measure the performance and usability of pages, including perceived load time, visual stability, and responsiveness to user input. If you're new to Core Web Vitals, these guides will familiarize you with how they work, and give you a starting point on how to optimize them.
LCP is a metric that measures the time it takes for the largest piece of content to appear on a page. Pages with low LCP signal to users that your page is loading quickly.
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CLS is a metric that measures layout stability by observing the page for unexpected changes in the layout. Pages with low CLS signal to users that a page's layout is stable and won't change unexpectedly as they try to interact with it.
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INP is a metric that measures how responsive a page is to user input. Pages with low INP signal to users that a page responds quickly when they interact with them, making your website feel more reliable and delightful to use.
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Each one of the Core Web Vitals metrics can be optimized to improve the user experience. Each of these guides goes in depth to show how you can apply proven techniques to improve the performance and reliability of your website so that users remain more engaged and less likely to leave.
Learn how to optimize LCP for your users so that they can see the most important content on your page as quickly as possible.
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Learn how to optimize CLS for your users so that they can expect that your website will remain stable and more usable.
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Learn how to optimize INP for your users so that they can expect that your website will respond quickly to interactions.
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The three Core Web Vitals metrics and how to optimize them are a great start, but there are even more topics around them to absorb. This content collection will help you to understand how to measure them, debug them, as well as some additional best practices for cookie notices, carousels, and other common user interface concerns.
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Improving performance doesn't just improve the user experience, it has the potential to help your business grow. Learn how these companies improved their Core Web Vitals and saw an increase in their business metrics.
Learn how Disney+ Hotstar increased weekly card views by 100% on living room devices by reducing INP by 61%.
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Learn how PubTech's Consent Management Platform reduced INP on their customers' websites by up to 64%, while also improving ad viewability by up to 1.5%
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Learn how Taboola used The Long Animation Frames API (LoAF) to improve INP up to 36% for its publisher partner websites.
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Baseline signals to web developers when web platform features can be safely used in all major browser engines. Here are some web performance-related features that are now Baseline Newly available.
The content-visibility CSS property became Baseline Newly available in September 2024.
The AVIF image format became Baseline Newly available in January 2024.
Module preload became Baseline Newly available in September 2023.
The Server-Timing HTTP response header became Baseline Newly available in March 2023.

Chrome DevTools is a suite of tools for developers to debug web applications, including tools to help you understand and improve the performance of your web applications.
The Network panel in DevTools shows you all the resources a page loads, and how long it took to load them. Learn how to use this panel to identify resource load-related performance issues.
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The Performance panel in DevTools shows you incredibly detailed information about the performance of a page during a recording session, including activity on the main thread, network activity, and additional tools that can help you to identify and fix performance problems.
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The Memory panel shows you how much memory is being used by a page's JavaScript. By learning how to use this panel, you can discover and fix memory-related issues caused by a page's JavaScript.
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