Question:
How can I optimise the performance of my Wix Studio site, given that PageSpeed Insights shows large delays caused by Wix’s JavaScript and other core resources?
Product:
Wix Studio Editor x Wix Stores
What are you trying to achieve:
I want to improve my site’s performance score on PageSpeed Insights, especially by reducing metrics like First Contentful Paint, Largest Contentful Paint, Total Blocking Time, and overall CPU time.
What have you already tried:
I ran a full analysis on PageSpeed Insights, which identified JavaScript execution times and other Wix-related scripts as the main performance bottlenecks. I have reached out to Wix support but would also like to know if the community has any additional advice or workarounds to optimize performance.
Additional information:
Key metrics from my PageSpeed Insights report include a mobile performance score of 30, FCP at 3.3s, LCP at 12.2s, TBT of 4,340 ms, and a JavaScript execution time of 13.7s. Most of the blocking time appears to be from Wix’s core scripts like react.production.min.js and thunderbolt-commons.bundle.min.js. Any insights on possible optimizations or if others have faced similar issues would be greatly appreciated.
Thank you for the suggestion, but unfortunately, the core issue seems to be related to the inherent JavaScript and resource load from Wix’s framework itself (e.g., react.production.min.js and thunderbolt-commons.bundle.min.js). Based on my PageSpeed Insights data, these core scripts are creating significant blocking times and delays, which a third-party speed optimization app may not be able to address.
If anyone has had success in optimizing core Wix resources or has other recommendations specific to handling these types of script-heavy frameworks, I’d appreciate the input.
The app fixes the render blocking issues, You should give it a trial.
https://pagespeed.web.dev/analysis/https-www-csolroastery-com-category-all-products/07bvxuk9wk?form_factor=mobile
tried it but it is still very bad i guess wix has to fix some issues asap . Whats the best way to bring this topic to the team?
Hey @Salih_Yilmaz!
Good questions 
- if you have a link to the site, it might help others in the community provide additional information and pointers on things that could help with the performance.
In general, here’s a few tips that should help out. First, when running PageSpeed Insights, be sure to do so in a new Incognito tab - it helps illuminate external factors like cache, or browser extensions. It’s also recommend to run the test a couple of times to get an average rating.
PageSpeed Insights uses aggressive CPU throttling in their simulatons on mobile devices, making it challenging to get a good score, and many other platforms struggle with this too, even top brands like Amazon or Apple struggle and receive low scroes - however, they have great field data.
I’d recommend if you haven’t already, to check out the Core Web Vitals Technology Report - https://cwvtech.report/ - which shows the median lighthouse score in Wix is higher than other platforms, which means you get a moderate score out of the box.
You’ll also see in the above report that 74% of sites built using Wix/Wix Studio pass Core Web Vitals in the US on mobile, and 64% of sites globally. Additionally, the difference in the percentage of mobile and desktop devices passing CWV in the US is similar.
With all that being said, in most cases, real-world usage is the most important. If you open the site on your phone and things load well, you’re all set to go. 
