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 Paint4.8 s0.3 s< 2.5 s
First Input Delay400 ms100 ms< 100ms
Cumulative Layout Shift00 0.1

Tracking scripts

All the tracking scripts on the site generated ~166 KB 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. 2 144 KB 3 21 KB 1 579 B 1 557 B


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.

adobe-caslon-pro-normal-3ee87b0a70ff86b80244ffdf6dd2636b.woff ~128 KB ~111 KB
MaisonNeueWEB-Bold-c9ca1128a49ec1e840b74a19ec5c9595.woff ~52 KB ~35 KB
MaisonNeueWEB-Book-a743c24df4952b49b9b31284d13c477f.woff ~52 KB ~34 KB

Convert font files to woff2

WOFF2 is considered to be the best font format for web use because it provides a good balance of file size and compatibility. Some specific reasons why WOFF2 is a good font format include:

  1. Small file size: WOFF2 is a compressed font format, which means that it has a smaller file size compared to other font formats like TTF or OTF. This is important for web use because smaller file sizes can help to reduce the amount of data that needs to be downloaded, leading to faster page load times.
  2. High-quality font rendering: WOFF2 provides high-quality font rendering, making it a good choice for use on the web.

It’s worth noting that WOFF2 is not the only font format that can be used on the web, and there may be cases where other formats like WOFF or TTF are more suitable, depending on the specific requirements of the website. However, for most cases, WOFF2 is considered to be the best font format for web use due to its combination of small file size, good browser support, and high-quality font rendering.


Largest Contentful Paint

Timing4.8 s0.3 s

Total Blocking Time

Timing570 ms50 ms

Speed Index

Timing5.6 s1.5 s

Time to Interactive

Timing6.1 s1.3 s

Max Potential First Input Delay

Timing400 ms100 ms

Properly size images

InsightPotential savings of 118 KiB

Reduce unused JavaScript

InsightPotential savings of 83 KiBPotential savings of 63 KiB

Reduce initial server response time

InsightRoot document took 980 msRoot document took 950 ms

Avoid serving legacy JavaScript to modern browsers

InsightPotential savings of 9 KiBPotential savings of 9 KiB

Uses efficient cache policy on static assets

Insight2 resources found2 resources found

Avoids an excessive DOM size

Insight590 elements632 elements

JavaScript execution time

Timing2.2 s0.5 s

Minimizes main-thread work

Timing5.0 s1.5 s