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Redirects introduce additional delays before the page can be loaded. Learn more.

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

Remove unused JavaScript to reduce bytes consumed by network activity. Learn more.

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

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

This is the largest contentful element painted within the viewport. Learn More

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

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. Learn more.

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

Descriptive link text helps search engines understand your content. Learn more.

The `unload` event does not fire reliably and listening for it can prevent browser optimizations like the Back-Forward Cache. Consider using the `pagehide` or `visibilitychange` events instead. Learn More

Some third-party scripts may contain known security vulnerabilities that are easily identified and exploited by attackers. Learn more.

Add `rel="noopener"` or `rel="noreferrer"` to any external links to improve performance and prevent security vulnerabilities. Learn more.

All sites should be protected with HTTPS, even ones that don't handle sensitive data. This includes avoiding mixed content, where some resources are loaded over HTTP despite the initial request being servedover HTTPS. HTTPS prevents intruders from tampering with or passively listening in on the communications between your app and your users, and is a prerequisite for HTTP/2 and many new web platform APIs. Learn more.

Image natural dimensions should be proportional to the display size and the pixel ratio to maximize image clarity. Learn more.

A maskable icon ensures that the image fills the entire shape without being letterboxed when installing the app on a device. Learn more. No manifest was fetched

A themed splash screen ensures a high-quality experience when users launch your app from their homescreens. Learn more. Failures: No manifest was fetched.

If you've already set up HTTPS, make sure that you redirect all HTTP traffic to HTTPS in order to enable secure web features for all your users. Learn more.

The browser address bar can be themed to match your site. Learn more. Failures: No manifest was fetched, No `<meta name="theme-color">` tag found.

A service worker enables your web app to be reliable in unpredictable network conditions. Learn more. No usable web app manifest found on page.

If you're building a Progressive Web App, consider using a service worker so that your app can work offline. Learn more.

All sites should be protected with HTTPS, even ones that don't handle sensitive data. This includes avoiding mixed content, where some resources are loaded over HTTP despite the initial request being servedover HTTPS. HTTPS prevents intruders from tampering with or passively listening in on the communications between your app and your users, and is a prerequisite for HTTP/2 and many new web platform APIs. Learn more.

The service worker is the technology that enables your app to use many Progressive Web App features, such as offline, add to homescreen, and push notifications. Learn more.

Browsers can proactively prompt users to add your app to their homescreen, which can lead to higher engagement. Learn more. Failures: No manifest was fetched.

Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more.

Disabling zooming is problematic for users with low vision who rely on screen magnification to properly see the contents of a web page. Learn more.

Adding ways to bypass repetitive content lets keyboard users navigate the page more efficiently. Learn more.

If a page doesn't specify a lang attribute, a screen reader assumes that the page is in the default language that the user chose when setting up the screen reader. If the page isn't actually in the default language, then the screen reader might not announce the page's text correctly. Learn more.

Low-contrast text is difficult or impossible for many users to read. Learn more.