Queensland University of Technology

The Index

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
30%
Desktop Performance
55%

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 Paint21.0 s5.1 s< 2.5 s
First Input Delay850 ms280 ms< 100ms
Cumulative Layout Shift0.0170 0.1

Tracking scripts

All the tracking scripts on the site generated ~1 MB of data

A tracking script is a code snippet designed to track the flow of visitors who visit a website. Media, advertising, and analytics organisations will provide a script to add to your website that sends data directly to their servers. This data can then be used to measure goals and conversions, analyse user behaviour, and influence advertising campaigns.

Consider how much of this data you actually need and use? How often do you review the analytics data, and does this inform genuine change? Are you actively running social media campaigns? Consider pausing or removing tracking scripts that aren’t being actively used.

googletagmanager.com 4 336 KB
google-analytics.com 9 114 KB
secure.quantserve.com 1 9 KB
bat.bing.com 3 13 KB
googleadservices.com 4 9 KB
snap.licdn.com 2 10 KB
redditstatic.com 1 8 KB
s.yimg.com 2 8 KB
aax-fe.amazon-adsystem.com 2 3 KB
cdn.pdst.fm 1 7 KB
clarity.ms 2 25 KB
analytics.tiktok.com 8 104 KB
sc-static.net 2 27 KB
ads-engagement.presage.io 1 531 B
googleads.g.doubleclick.net 8 14 KB
google.com 10 9 KB
alb.reddit.com 1 603 B
google.com.au 4 2 KB
tr.snapchat.com 5 3 KB
cdn.linkedin.oribi.io 2 925 B
px.ads.linkedin.com 3 3 KB
pixel.quantserve.com 1 575 B
pixel.tapad.com 2 2 KB
z.clarity.ms 4 882 B
linkedin.com 1 2 KB
sp.analytics.yahoo.com 1 928 B
s.amazon-adsystem.com 36 23 KB
stats.g.doubleclick.net 2 1 KB
ib.adnxs.com 2 1 KB
match.360yield.com 4 3 KB
rtb-csync.smartadserver.com 1 730 B
aa.agkn.com 1 906 B
dsum-sec.casalemedia.com 2 2 KB
x.bidswitch.net 1 235 B
tags.bluekai.com 1 726 B
ups.analytics.yahoo.com 2 2 KB
t.myvisualiq.net 2 1 KB
amazon.partners.tremorhub.com 1 654 B
public-prod-dspcookiematching.dmxleo.com 1 186 B
cms.analytics.yahoo.com 1 1 KB
ads.stickyadstv.com 2 1 KB
imdb.com 1 1 KB
beacon.krxd.net 1 444 B
usersync.samplicio.us 1 282 B
ads.samba.tv 1 992 B
pixel.rubiconproject.com 1 841 B
dpm.demdex.net 2 2 KB
odr.mookie1.com 1 993 B
c1.adform.net 2 2 KB
sync.search.spotxchange.com 2 1 KB
bs.serving-sys.com 1 879 B
cm.g.doubleclick.net 2 1 KB
usermatch.krxd.net 1 221 B
sb.scorecardresearch.com 2 1 KB
us-u.openx.net 4 2 KB
ssum-sec.casalemedia.com 2 2 KB
eb2.3lift.com 2 1 KB
uipglob.semasio.net 2 1 KB
image2.pubmatic.com 1 704 B
loadus.exelator.com 2 2 KB
lciapi.ninthdecimal.com 1 800 B
pi.ispot.tv 1 626 B
image6.pubmatic.com 2 1 KB
sync.taboola.com 1 493 B
lm.serving-sys.com 1 284 B
lib-us-1.brilliantcollector.com 5 2 KB
c.clarity.ms 2 2 KB
connect.facebook.net 3 247 KB
c.bing.com 1 1 KB
facebook.com 2 656 B

Opportunities

Optimise images

By optimising the following images, roughly 1,020 KB could be removed from the transfer size, about 27%. This would reduce the CO2 generated per page load from 0.97g grams to 0.7 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.
education-precinct-venue.jpg 283 KB 8% 243 KB
uv-tech.jpg 271 KB 7% 54 KB
qut-country.jpg 218 KB 6% 143 KB
start-qut-info-webinar.jpg 196 KB 5% 42 KB
research-participation-laptop.jpg 177 KB 5% 97 KB
facilities-merf-2.jpg 122 KB 3% 78 KB
diamond-researchers.jpg 113 KB 3% 97 KB
qut-advice-night.jpg 112 KB 3% 33 KB
gardens-point-campus-open-day.jpg 110 KB 3% 41 KB
international-student-support.jpg 80 KB 2% 50 KB
nadine-ostern.jpg 73 KB 2% 58 KB
arc-linkage-grants-2.jpg 72 KB 2% 28 KB
mia-mead-event-virtual-open-day.jpg 71 KB 2% 46 KB
library-campus.jpg 59 KB 2% 9 KB

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.

Typekit: l ~34 KB ~17 KB
Typekit: l ~34 KB ~16 KB
Typekit: l ~33 KB ~15 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
use.typekit.netl
use.typekit.netl
use.typekit.netl

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.

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
Score14%86%
Timing4.6 s1.0 s

Largest Contentful Paint

MobileDesktop
Score0%8%
Timing21.0 s5.1 s

Total Blocking Time

MobileDesktop
Score10%64%
Timing1,790 ms270 ms

Speed Index

MobileDesktop
Score2%3%
Timing13.7 s5.1 s

Time to Interactive

MobileDesktop
Score1%44%
Timing22.2 s4.8 s

Max Potential First Input Delay

MobileDesktop
Score0%41%
Timing850 ms280 ms

First Meaningful Paint

MobileDesktop
Score33%81%
Timing4.8 s1.1 s

Eliminate render-blocking resources

MobileDesktop
Score28%67%
InsightPotential savings of 2,650 msPotential savings of 450 ms

Defer offscreen images

MobileDesktop
Score46%100%
InsightPotential savings of 697 KiBPotential savings of 429 KiB

Minify CSS

MobileDesktop
Score85%97%
InsightPotential savings of 19 KiBPotential savings of 19 KiB

Minify JavaScript

MobileDesktop
Score48%87%
InsightPotential savings of 75 KiBPotential savings of 75 KiB

Reduce unused CSS

MobileDesktop
Score46%87%
InsightPotential savings of 180 KiBPotential savings of 164 KiB

Reduce unused JavaScript

MobileDesktop
Score0%47%
InsightPotential savings of 742 KiBPotential savings of 736 KiB

Efficiently encode images

MobileDesktop
Score41%91%
InsightPotential savings of 313 KiBPotential savings of 436 KiB

Serve images in next-gen formats

MobileDesktop
Score13%80%
InsightPotential savings of 865 KiBPotential savings of 1,020 KiB

Enable text compression

MobileDesktop
Score100%97%
InsightPotential savings of 4 KiBPotential savings of 4 KiB

Reduce initial server response time

MobileDesktop
GradeFailFail
InsightRoot document took 1,260 msRoot document took 1,390 ms

Avoid enormous network payloads

MobileDesktop
Score65%57%
InsightTotal size was 3,521 KiBTotal size was 3,754 KiB

Serve static assets with an efficient cache policy

MobileDesktop
Score10%10%
Insight66 resources found59 resources found

Avoid an excessive DOM size

MobileDesktop
Score26%26%
Insight1,820 elements1,820 elements

Reduce JavaScript execution time

MobileDesktop
Score23%75%
Timing6.1 s2.1 s

Minimize main-thread work

MobileDesktop
Score5%59%
Timing9.2 s3.5 s

Ensure text remains visible during webfont load

MobileDesktop
GradeFailFail

Minimize third-party usage

MobileDesktop
GradeFailPass
InsightThird-party code blocked the main thread for 980 msThird-party code blocked the main thread for 210 ms

Does not use passive listeners to improve scrolling performance

MobileDesktop
GradeFailFail

Image elements do not have explicit width and height

MobileDesktop
GradeFailFail