Aristocrat Leisure Ltd

The Index


Google Lighthouse Performance

The Google Lighthouse performance score is a metric that measures the speed and performance of a website. It’s an overall score that ranges from 0 to 100 and is generated based on a number of different performance metrics, such as the time it takes for a website to load, the time it takes for a website to become interactive, the size of the resources used by the website, and other factors that impact the user experience.

A high performance score in Google Lighthouse indicates that a website is fast and responsive, which can lead to a better user experience and improved search engine rankings. On the other hand, a low performance score can indicate that a website is slow and unresponsive, and can negatively impact the user experience.

Mobile Performance
Desktop Performance

Core Web Vitals

Core Web Vitals are a set of specific factors that Google considers important in a webpage’s overall user experience. Core Web Vitals are made up of three specific page speed and user interaction measurements: Largest Contentful PaintFirst Input Delay, and Cumulative Layout Shift.

Largest Contentful Paint15.0 s2.8 s< 2.5 s
First Input Delay640 ms270 ms< 100ms
Cumulative Layout Shift0.0070.001 0.1


Remove autoplaying or preloaded media files

By removing 21 autoplaying or preloaded videos, roughly 17.5 MB could be removed from the page load.

This would reduce the page transfer size by 72% and reduce the pages emissions from 6.4 grams of CO2 to 1.77 grams of CO2.

Autoplaying videos can have a negative impact on the user experience for several reasons:

  1. Increased data usage: Autoplaying videos can consume a lot of data, especially if they are set to play in high definition. This can be a problem for users with limited data plans or slow connections, who may experience slow or interrupted playback.
  2. Annoyance factor: Autoplaying videos can be annoying for users, especially if they are accompanied by sound. This can lead to a negative perception of the website and decreased engagement.
  3. Reduced accessibility: Autoplaying videos can be a problem for users with accessibility needs, such as users who are blind or have hearing difficulties.
  4. Increased page load time: Autoplaying videos can increase the overall page load time, leading to a slower user experience.
  5. Decreased battery life: Autoplaying videos can consume a lot of battery power, especially on mobile devices, leading to reduced battery life.

In order to minimise the impact of autoplaying videos on the user experience, it is recommended to use them sparingly and only when necessary. It is also important to provide users with the option to turn off autoplaying videos and to allow them to control the playback of videos on the page. Additionally, videos should be optimised for performance and should be accompanied by captions or transcripts to improve accessibility.

segment-1.m4s 4 MB 18%
segment-1.m4s 4 MB 18%
segment-1.m4s 3 MB 13%
segment-1.m4s 2 MB 9%
segment-1.m4s 1 MB 5%
segment-1.m4s 431 KB 2%
segment-1.m4s 303 KB 1%
1191f55b.mp4 245 KB 1%
095802dd.mp4 222 KB 1%
095802dd.mp4 222 KB 1%
d097433c.mp4 182 KB 1%
d097433c.mp4 182 KB 1%
b878e581.mp4 176 KB 1%
b878e581.mp4 176 KB 1%
61ad0611.mp4 169 KB 1%
61ad0611.mp4 169 KB 1%
0105e88d.mp4 3 KB 0%
0d0377c6.mp4 3 KB 0%
0d0377c6.mp4 3 KB 0%
45b1151d.mp4 3 KB 0%
45b1151d.mp4 3 KB 0%

Subset large font files

Fonts should be subsetted to reduce the file size, improve performance, and reduce emissions. Subsetting a font involves removing any characters that are not needed for a particular use case, resulting in a smaller file size and faster page load times. Some specific reasons why fonts should be subsetted include:

  1. Reduced file size: Subsetting a font removes any unused characters, which can result in a smaller file size. This can help to reduce the amount of data that needs to be downloaded, leading to faster page load times and lower emissions.
  2. Improved performance: Fonts that are subsetted are faster to load and render than fonts that are not subsetted. This can help to improve the overall performance of a website, leading to a better user experience.

Overall, subsetting fonts is a good practice for anyone looking to optimize the performance and reduce the emissions of a website of a website.

cY9cfjeOW0NHpmOQXranrbDyu7hADpKTZhPo.woff2 ~30 KB ~12 KB

Remove third party font files

Font files should be loaded from the same hosting as the website because

  1. Increased loading time: Third-party sub-resources, such as scripts, fonts, or images, need to be downloaded from a separate server before they can be displayed on the website. This can increase the overall loading time of the page, leading to a slower user experience.
  2. Dependence on external servers: The loading of third-party subresources is dependent on the availability and performance of the external servers that host them. If these servers are slow or unavailable, it can result in slow page loading times or even errors.
  3. Increased risk of security threats: Third-party subresources can introduce security risks to a website, as they can contain malicious code or be used to track user activity.

Replace jQuery and jQuery libraries with more modern code

jQuery is a popular and widely-used JavaScript library that simplifies web development by providing a set of tools and functions to interact with HTML documents, handle events, create animations, and make asynchronous HTTP requests.

In the past, jQuery was a very popular choice for web development because it simplified many common tasks and provided a consistent and cross-browser-compatible API. However, with the advancement of modern web technologies and improvements in browser capabilities, the need for jQuery has decreased.

Many modern web frameworks and libraries, such as React and Angular, provide their own set of tools for handling common tasks and interacting with the DOM, making jQuery less necessary in many cases. The Javascript engine in modern browsers have also become more consistent in the feature implementations often eliminating the need for a library like jQuery.

jQuery represents an opportunity because:

  1. Performance: While jQuery is a powerful and useful library, it can slow down website performance due to its large size and complex code. Modern browsers have also improved their native support for many of the features that jQuery provides, reducing the need for it.
  2. Maintainability: jQuery code can be difficult to maintain and update, particularly as web technologies evolve and change. This can make it harder for developers to keep up with best practices and standards for web development.
  3. Accessibility: Some jQuery plugins and features can create accessibility issues, particularly for users who rely on assistive technologies. This can make it harder for people with disabilities to use and access websites.
jquery.min.js 36 KB
jquery-migrate.min.js 5 KB

First Contentful Paint

First Contentful Paint (FCP) is a performance metric that measures the time it takes for the first piece of content to be rendered on the screen when a user navigates to a web page. This content can be any visual element on the page, such as text, images, or a background color.

FCP is important because it directly affects the perceived speed of a website, and can impact user engagement and conversion rates. A faster FCP can lead to a better user experience and improved performance.

Here are a few ways you can optimise your FCP:

  1. Optimise images: Large, unoptimised images can slow down a page’s FCP. You can optimise images by compressing them, reducing their dimensions, and choosing the right format for each image.
  2. Minimise HTTP requests: Each resource requested by a web page, such as images, scripts, and stylesheets, requires a separate HTTP request. Minimising the number of HTTP requests can help to reduce the time it takes for a page to render.
  3. Prioritize critical content: Prioritizing critical content, such as above-the-fold content, can help to ensure that users see something on the screen quickly, even if the rest of the page is still loading.
  4. Reduce server response time: A slow server response time can significantly impact FCP. Optimizing server-side code and server settings can help to reduce response times and improve FCP.
  5. Use a performance monitoring tool: There are many tools available that can help you monitor your website’s performance, including FCP. These tools can help you identify performance issues and track your progress as you implement optimizations.
Timing4.7 s1.1 s

Time to Interactive

Timing37.0 s8.4 s

Speed Index

Timing29.3 s9.1 s

Total Blocking Time

Timing3,100 ms650 ms

Largest Contentful Paint

Timing15.0 s2.8 s

Max Potential First Input Delay

Timing640 ms270 ms

First Meaningful Paint

Timing4.7 s1.4 s

Eliminate render-blocking resources

InsightPotential savings of 2,910 msPotential savings of 630 ms

Properly size images

InsightPotential savings of 1,615 KiB

Defer offscreen images

InsightPotential savings of 1,816 KiBPotential savings of 1,136 KiB

Minify CSS

InsightPotential savings of 303 KiBPotential savings of 303 KiB

Minify JavaScript

InsightPotential savings of 201 KiBPotential savings of 201 KiB

Reduce unused CSS

InsightPotential savings of 416 KiBPotential savings of 413 KiB

Reduce unused JavaScript

InsightPotential savings of 193 KiBPotential savings of 194 KiB

Reduce initial server response time

InsightRoot document took 1,030 msRoot document took 960 ms

Avoid enormous network payloads

InsightTotal size was 17,372 KiBTotal size was 24,815 KiB

Serve static assets with an efficient cache policy

Insight114 resources found122 resources found

Avoid an excessive DOM size

Insight3,223 elements3,307 elements

Reduce JavaScript execution time

Timing10.9 s4.2 s

Minimize main-thread work

Timing20.9 s8.6 s

Reduce the impact of third-party code

InsightThird-party code blocked the main thread for 4,690 msThird-party code blocked the main thread for 540 ms

Some third-party resources can be lazy loaded with a facade

Insight1 facade alternative available1 facade alternative available

Does not use passive listeners to improve scrolling performance


Image elements do not have explicit width and height