Insights

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
29%
Desktop Performance
79%

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.

VitalMobileDesktopTarget
Largest Contentful Paint32.3 s2.8 s< 2.5 s
First Input Delay230 ms20 ms< 100ms
Cumulative Layout Shift0.1220.003 0.1

Opportunities

Optimise images

By optimising the following images, roughly 3 MB could be removed from the transfer size, about 61%. This would reduce the CO2 generated per page load from 1.09g grams to 0.43 grams.

Images should be optimised for the web for several reasons:

  1. Reduced file size: Optimizing images can result in a smaller file size, which can help to reduce the amount of data that needs to be downloaded. This can lead to faster page load times and improved performance.
  2. Improved user experience: Optimising images can help to improve the overall user experience, as pages with optimised images load faster and are more responsive.
  3. Lower emissions: Optimising images can help to reduce the emissions associated with data transfer, as less data needs to be transmitted over the network.
  4. Better accessibility: Optimising images can make them more accessible to users with slower connections or limited data plans.
Screenshot-2023-02-01-131052.png 1 MB 34% 1 MB
IMG_7364-scaled.jpg 496 KB 12% 220 KB
IMG_7364-scaled.jpg 496 KB 12% 220 KB
slide-10.jpg 414 KB 10% 168 KB
slide-10.jpg 414 KB 10% 168 KB
slide-2.jpg 333 KB 8% 162 KB
slide-6.jpg 273 KB 6% 86 KB
slide-7.jpg 232 KB 5% 93 KB
maths-day-1024x684.jpg 100 KB 2% 45 KB
Event-Cal-Banner-Template_2560x1709px-2-1024x684.jpg 77 KB 2% 35 KB
shutterstock_1702499890-1024x683.jpg 69 KB 2% 31 KB

Replace icon font files

Font icons can have a negative impact on performance and emissions because they can increase the size of the page and the amount of data that needs to be downloaded. Some specific reasons why font icons can be bad for performance and emissions include:

  1. Increased file size: Font icons are typically included as part of a web font, which can be a large file that needs to be downloaded. This can increase the overall size of the page, leading to slower load times and higher emissions.
  2. Inefficient rendering: Web fonts are sometimes loaded and rendered inefficiently, which can result in slow performance and higher emissions.
  3. Unused icons: Font icons often include a large number of icons that may not be used on a particular page, increasing the file size and leading to inefficient use of resources.

While icon fonts are still widely used on the web, and they can be a useful tool for adding icons to a website. it is a dated practice when there are better options such as SVG icons, which can be more efficient and have a lower impact on performance and emissions.

FontSize
fa-solid-900.woff2134 KB
fa-regular-400.woff2165 KB
fa-brands-400.woff275 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.
HostFont
fonts.gstatic.comKFOmCnqEu92Fr1Mu4mxKKTU1Kg.woff2
fonts.gstatic.comKFOlCnqEu92Fr1MmWUlfBBc4AMP6lQ.woff2

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.
MobileDesktop
Score7%93%
Timing5.3 s0.9 s

Largest Contentful Paint

MobileDesktop
Score0%40%
Timing32.3 s2.8 s

Total Blocking Time

MobileDesktop
Score23%100%
Timing1,100 ms0 ms

Cumulative Layout Shift

MobileDesktop
Score84%100%
Timing0.1220.003

Speed Index

MobileDesktop
Score0%45%
Timing29.2 s2.4 s

Time to Interactive

MobileDesktop
Score0%100%
Timing27.2 s0.9 s

Max Potential First Input Delay

MobileDesktop
Score57%100%
Timing230 ms20 ms

First Meaningful Paint

MobileDesktop
Score25%93%
Timing5.3 s0.9 s

Eliminate render-blocking resources

MobileDesktop
Score27%100%
InsightPotential savings of 2,680 msPotential savings of 0 ms

Properly size images

MobileDesktop
Score48%87%
InsightPotential savings of 150 KiBPotential savings of 214 KiB

Defer offscreen images

MobileDesktop
Score39%100%
InsightPotential savings of 291 KiB

Minify CSS

MobileDesktop
Score88%100%
InsightPotential savings of 3 KiBPotential savings of 7 KiB

Minify JavaScript

MobileDesktop
Score75%100%
InsightPotential savings of 56 KiB

Reduce unused CSS

MobileDesktop
Score38%87%
InsightPotential savings of 155 KiBPotential savings of 179 KiB

Reduce unused JavaScript

MobileDesktop
Score0%100%
InsightPotential savings of 744 KiB

Efficiently encode images

MobileDesktop
Score88%97%
InsightPotential savings of 33 KiBPotential savings of 33 KiB

Serve images in next-gen formats

MobileDesktop
Score0%38%
InsightPotential savings of 2,283 KiBPotential savings of 2,189 KiB

Reduce initial server response time

MobileDesktop
GradeFailFail
InsightRoot document took 5,890 msRoot document took 1,100 ms

Avoid serving legacy JavaScript to modern browsers

MobileDesktop
Score88%100%
InsightPotential savings of 56 KiB

Avoid enormous network payloads

MobileDesktop
Score8%43%
InsightTotal size was 6,127 KiBTotal size was 4,229 KiB

Serve static assets with an efficient cache policy

MobileDesktop
Score0%0%
Insight88 resources found44 resources found

Avoid an excessive DOM size

MobileDesktop
Score9%8%
Insight2,416 elements2,490 elements

JavaScript execution time

MobileDesktop
Score32%100%
Timing5.0 s0.0 s

Minimizes main-thread work

MobileDesktop
Score2%100%
Timing11.7 s0.6 s

All text remains visible during webfont loads

MobileDesktop
GradeFailPass

Minimize third-party usage

MobileDesktop
GradeFailPass
InsightThird-party code blocked the main thread for 470 msThird-party code blocked the main thread for 0 ms

Uses passive listeners to improve scrolling performance

MobileDesktop
GradeFailPass

Image elements do not have explicit width and height

MobileDesktop
GradeFailFail