Jb51.net Site Title
Jb51.net Meta Description
Jb51.net Test Results
Jb51.net Mobile Performance: 46/100
These suggestions can help your page load faster. They don't directly affect the Performance score.
Defer offscreen images. Potential savings of 1,711 KiB
Consider lazy-loading offscreen and hidden images after all critical resources have finished loading to lower time to interactive. Learn more.
Serve images in next-gen formats. Potential savings of 1,320 KiB
Image formats like JPEG 2000, JPEG XR, and WebP often provide better compression than PNG or JPEG, which means faster downloads and less data consumption. Learn more.
Efficiently encode images. Potential savings of 825 KiB
Optimized images load faster and consume less cellular data. Learn more.
Properly size images. Potential savings of 185 KiB
Serve images that are appropriately-sized to save cellular data and improve load time. Learn more.
Reduce initial server response time. Root document took 1,750 ms
Keep the server response time for the main document short because all other requests depend on it. Learn more.
Eliminate render-blocking resources. Potential savings of 780 ms
Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles. Learn more.
Enable text compression. Potential savings of 40 KiB
Text-based resources should be served with compression (gzip, deflate or brotli) to minimize total network bytes. Learn more.
More information about the performance of your application. These numbers don't directly affect the Performance score.
For users on slow connections, external scripts dynamically injected via `document.write()` can delay page load by tens of seconds. Learn more.
Serve static assets with an efficient cache policy
67 resources found
A long cache lifetime can speed up repeat visits to your page. Learn more.
Avoid an excessive DOM size
A large DOM will increase memory usage, cause longer style calculations, and produce costly layout reflows. Learn more.
Minimize main-thread work
Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn more
Avoid long main-thread tasks
6 long tasks found
Lists the longest tasks on the main thread, useful for identifying worst contributors to input delay. Learn more
Keep request counts low and transfer sizes small
134 requests • 2,169 KiB
To set budgets for the quantity and size of page resources, add a budget.json file. Learn more.
Largest Contentful Paint element
1 element found
This is the largest contentful element painted within the viewport. Learn More
Avoid chaining critical requests
13 chains found
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.
Jb51.net Mobile SEO: 83/100
Make sure your pages are mobile friendly so users don’t have to pinch or zoom in order to read the content pages. Learn more.
Tap targets are not sized appropriately
84% appropriately sized tap targets
Interactive elements like buttons and links should be large enough (48x48px), and have enough space around them, to be easy enough to tap without overlapping onto other elements. Learn more.
Crawling and Indexing
To appear in search results, crawlers need access to your app.
Links are not crawlable
Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn More
Content Best Practices
Format your HTML in a way that enables crawlers to better understand your app’s content.
Jb51.net Mobile Best Practices: 62/100
Trust and Safety
Does not use HTTPS
3 insecure requests found
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.
Links to cross-origin destinations are unsafe
Add `rel="noopener"` or `rel="noreferrer"` to any external links to improve performance and prevent security vulnerabilities. Learn more.
4 vulnerabilities detected
Some third-party scripts may contain known security vulnerabilities that are easily identified and exploited by attackers. Learn more.
Jb51.net Mobile Progressive Web App: 21/100
Does not set a theme color for the address bar.
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.
Does not provide a valid `apple-touch-icon`
For ideal appearance on iOS when users add a progressive web app to the home screen, define an `apple-touch-icon`. It must point to a non-transparent 192px (or 180px) square PNG. Learn More.
Manifest doesn't have a maskable icon
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
Is not configured for a custom splash screen
A themed splash screen ensures a high-quality experience when users launch your app from their homescreens. Learn more. Failures: No manifest was fetched.
Does not use HTTPS
3 insecure requests found
Web app manifest does not meet the installability requirements
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.
Does not register a service worker that controls page and `start_url`
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.
Fast and reliable
Current page does not respond with a 200 when offline
If you're building a Progressive Web App, consider using a service worker so that your app can work offline. Learn more.
`start_url` does not respond with a 200 when offline
A service worker enables your web app to be reliable in unpredictable network conditions. Learn more. No usable web app manifest found on page.
Page load is not fast enough on mobile networks
Interactive at 10.7 s
A fast page load over a cellular network ensures a good mobile user experience. Learn more. Your page loads too slowly and is not interactive within 10 seconds. Look at the opportunities and diagnostics in the "Performance" section to learn how to improve.
Jb51.net Mobile Accessibility: 36/100
These are opportunities to improve keyboard navigation in your application.
These items highlight common accessibility best practices.
`[user-scalable="no"]` is used in the `<meta name="viewport">` element or the `[maximum-scale]` attribute is less than 5.
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.
These are opportunities to improve the legibility of your content.
Names and labels
These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.
Links do not have a discernible name
Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn more.
Image elements do not have `[alt]` attributes
Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more.
Form elements do not have associated labels
Labels ensure that form controls are announced properly by assistive technologies, like screen readers. Learn more.
Internationalization and localization
These are opportunities to improve the interpretation of your content by users in different locales.
`<html>` element does not have a `[lang]` attribute
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.