First Meaningful Paint measures when the primary content of a page is visible

The Critical Request Chains below show you what resources are loaded with a high priority. Consider reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load

Speed Index shows how quickly the contents of a page are visibly populated

Lists the longest tasks on the main thread, useful for identifying worst contributors to input delay

First Contentful Paint marks the time at which the first text or image is painted

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity

Largest Contentful Paint marks the time at which the largest text or image is painted

Time to Interactive is the amount of time it takes for the page to become fully interactive

Third-party code can significantly impact load performance. Limit the number of redundant third-party providers and try to load third-party code after your page has primarily finished loading

Network round trip times (RTT) have a large impact on performance. If the RTT to an origin is high, it's an indication that servers closer to the user could improve performance

To set budgets for the quantity and size of page resources, add a budget.json file

A long cache lifetime can speed up repeat visits to your page

Polyfills and transforms enable legacy browsers to use new JavaScript features. However, many aren't necessary for modern browsers. For your bundled JavaScript, adopt a modern script deployment strategy using module/nomodule feature detection to reduce the amount of code shipped to modern browsers, while retaining support for legacy browsers

This is the largest contentful element painted within the viewport

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Optimized images load faster and consume less cellular data

Minifying CSS files can reduce network payload sizes

The maximum potential First Input Delay that your users could experience is the duration of the longest task

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this

Large network payloads cost users real money and are highly correlated with long load times

Keep the server response time for the main document short because all other requests depend on it

Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles

Server latencies can impact web performance. If the server latency of an origin is high, it's an indication the server is overloaded or has poor backend performance

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this

Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds

Serve images that are appropriately-sized to save cellular data and improve load time

Cumulative Layout Shift measures the movement of visible elements within the viewport

Image formats like WebP and AVIF often provide better compression than PNG or JPEG, which means faster downloads and less data consumption

Minifying JavaScript files can reduce payload sizes and script parse time

These DOM elements contribute most to the CLS of the page

If the LCP element is dynamically added to the page, you should preload the image in order to improve LCP

A large DOM will increase memory usage, cause longer [style calculations](https://developers.google.com/web/fundamentals/performance/rendering/reduce-the-scope-and-complexity-of-style-calculations), and produce costly [layout reflows](https://developers.google.com/speed/articles/reflow)

Text-based resources should be served with compression (gzip, deflate or brotli) to minimize total network bytes

Animations which are not composited can be janky and increase CLS

Interactive elements like buttons and links should be large enough (48x48px), or have enough space around them, to be easy enough to tap without overlapping onto other elements

Server latencies can impact web performance. If the server latency of an origin is high, it's an indication the server is overloaded or has poor backend performance

First Contentful Paint marks the time at which the first text or image is painted

Animations which are not composited can be janky and increase CLS

To set budgets for the quantity and size of page resources, add a budget.json file

Large network payloads cost users real money and are highly correlated with long load times

Time to Interactive is the amount of time it takes for the page to become fully interactive

A long cache lifetime can speed up repeat visits to your page

Minifying CSS files can reduce network payload sizes

Minifying JavaScript files can reduce payload sizes and script parse time

Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles

Optimized images load faster and consume less cellular data

A large DOM will increase memory usage, cause longer [style calculations](https://developers.google.com/web/fundamentals/performance/rendering/reduce-the-scope-and-complexity-of-style-calculations), and produce costly [layout reflows](https://developers.google.com/speed/articles/reflow)

The Critical Request Chains below show you what resources are loaded with a high priority. Consider reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this

Font sizes less than 12px are too small to be legible and require mobile visitors to “pinch to zoom” in order to read. Strive to have >60% of page text ≥12px

Image formats like WebP and AVIF often provide better compression than PNG or JPEG, which means faster downloads and less data consumption

Sum of all time periods between FCP and Time to Interactive, when task length exceeded 50ms, expressed in milliseconds

If the LCP element is dynamically added to the page, you should preload the image in order to improve LCP

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity

Serve images that are appropriately-sized to save cellular data and improve load time

Third-party code can significantly impact load performance. Limit the number of redundant third-party providers and try to load third-party code after your page has primarily finished loading

Largest Contentful Paint marks the time at which the largest text or image is painted

Text-based resources should be served with compression (gzip, deflate or brotli) to minimize total network bytes

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity

Lists the longest tasks on the main thread, useful for identifying worst contributors to input delay

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Keep the server response time for the main document short because all other requests depend on it

Network round trip times (RTT) have a large impact on performance. If the RTT to an origin is high, it's an indication that servers closer to the user could improve performance

Polyfills and transforms enable legacy browsers to use new JavaScript features. However, many aren't necessary for modern browsers. For your bundled JavaScript, adopt a modern script deployment strategy using module/nomodule feature detection to reduce the amount of code shipped to modern browsers, while retaining support for legacy browsers

These DOM elements contribute most to the CLS of the page

This is the largest contentful element painted within the viewport

First Meaningful Paint measures when the primary content of a page is visible

Speed Index shows how quickly the contents of a page are visibly populated

The maximum potential First Input Delay that your users could experience is the duration of the longest task