In Google Lighthouse the headline results are colour coded and scored out of 100, making it easy to understand at a glance whether your site is ‘good’ or ‘bad’ (according to Google). Of course, to delve deeper into what the issues are and get a plan together of how to fix them, then you need some technical expertise. Using a CMS, like Sitecore, will help provide a framework to ensure that the basic 'furniture' is always in place, but it is up to the skill of the developers to ensure that the many conditions Google looks for are met.

If you need help to understand the results and the implications of what Google Lighthouse is reporting, then get in touch with us. We can also help you with a roadmap to improvement as well as provide the technical know-how to get your site loading screamingly fast. If the site isn't healthy in Google's (and Bing's) eyes then you are handicapping your site's search engine performance even before you get around to the challenges of writing interesting, relevant content for your audiences.

Google Lighthouse results screendump

Example of a Google Lighthouse audit

Google Lighthouse has been designed to measure and report on five key aspects of website performance.

  1. Performance  
  2. Accessibility  
  3. Best practices
  4. SEO
  5. Progressive Web Apps

If Google has taken the time to design and build a tool to measure these five things, then you can bet Google thinks they are important. If they are important to Google, then you can assume they're highly relevant when it comes to deciding where your Sitecore website's pages will rank in Google’s Search Engine Results Pages (SERPS)! If you use the tool as a guide to improve your Sitecore website, then this can only help improve your pages’ rankings. You certainly won’t risk being penalised anymore.

Google Lighthouse measures website performance

The speed at which your pages load on a visitor’s device is important. Google/SOASTA Research 2017 tells us that as a page load time goes from 1 to 3 seconds then the probability of a bounce (a lost visitor) increases by 32%. Google knows this too, and page speed is very much part of the search engine ranking algorithm. The slower your site, the less chance there is that Google will rank it highly.

You can't assume that all your visitors will be sitting at home on a super-fast broadband connection. Many visitors now arrive at your site from a mobile device and want the site to load just as if they were browsing from home and the office. That means it must load fast and it must look good.

There are many tips and tricks to optimise the speed at which a page loads.

Through the Chrome Developer tools interface you can see that you can use Google Lighthouse to test your site, simulating a visitor on a mobile or a desktop, and simulate connection speeds by “throttling” the connection as a slow or fast 4G or with no throttling (i.e. a fast broadband connection).

We discussed in our article "Dead website walking" how imagery can be a speed killer on a website, but there is more to speed than just imagery. Google Lighthouse helps by measuring, displaying and explaining a host of performance elements. The results are broken down into Metrics, Opportunities, and Diagnostics. The detailed explanation of these are for another day, but you will be able to get a good understanding of what makes your tick from these results. The items in the Metrics section contribute to your score. Your site’s results are compared to real website data in the field. Some factors are weighted more heavily than others. Simply put, how fast your site loads in a browser isn't a function of the CMS, like Sitecore, but actually a function of how the pages are constructed combined with the infrastructure the CMS is installed on.


Websites should be designed and built in such a way that they don't exclude those with disabilities from being able to use your site. There are international standards and government mandates that define what is needed for a site to be accessible. Accessibility supports social inclusion for those with disabilities, as well as older people and those with limited online connectivity. Making your website accessible makes good business sense but is also required by law.

A Google Lighthouse report will show you where you are not meeting accessibility guidelines. It will also show you a list of manual text steps you should carry out as automated test tools cannot cover all accessibility guidelines. The score you get is a weighted average of all the audits; the bigger the weight the bigger the impact on the score. There are no partial scores, if there is an issue with the audit characteristic then it is scored zero.

Best practices

A properly built website will adhere to certain ways of doing things that have become accepted practice over the years. Some of these topics are security-based, some documentation based, and some performance-based. Not following these guidelines can open up the site to known cyber attack methods. These best practices are hygiene factors and easily complied with. Unlike Performance and Accessibility scores, these scores are equally weighted.

Search Engine Optimisation (SEO)

The checks carried out in this section ensure your Sitecore website's pages are optimised for search engine results ranking. You will be alerted when you deviate from content best practices and when there are issues with the site. We produced an interesting article about SEO tips for your Sitecore website, which is worth a read. You can add bespoke rules into the Sitecore content validation feature to ensure that SEO best practices are followed, for example, setting a meta description character limit.

Progressive Web Apps

The Google Lighthouse tool can help you validate that all the necessary aspects of a Progressive Web App (PWA) are in place. Your PWA should be:

  • Fast and reliable (even offline)
  • Installable so you can load it onto your mobile device’s home screen.  If you want to read more about Progressive Web Apps, then you can read our quick guide to PWAs
  • Optimised to give a great mobile experience

Quality Assurance and DevOps

You can use Google Lighthouse’s Command Line Interface (CLI), or integrate Lighthouse into your continuous integration systems as a node module, and make it an integral part of the build and test process. Nothing should get deployed that degrades the performance of your site.

We'll write a piece about how we have utilised Google Lighthouse as part of our automated Quality Assurance (QA) mechanisms in a later article. If you aren’t quite there yet in your DevOps journey then you can add the Lighthouse Tool to your browser as a Chrome extension and/or access it directly through the Google Dev Tools menu in Chrome.

How can we help?

If you’ve got this far, then thank you for reading, hopefully, it has been enlightening. Codehouse can help make your web presence felt. We can not only design and build an engaging Sitecore website, but we can also work with you to continually optimise your online presence and improve your visitors' digital experience. We do this by building a measurement framework and iteratively improving performance.

We can also help generate and implement new ideas for how to best serve your company’s stakeholders, be they site visitors, prospects, leads, customers and colleagues. A website is more than just an online brochure or a project, it’s a web product. Make sure that your website investment is fully leveraged by taking the time to ensure you invest in it going forward rather than just expecting what you went live with to see you right for the next 5 years.

As well as being experts in Sitecore we're also experts in SEO - two ingredients that will make your website sing. Get in touch to find out more.