Details of how Chrome User Experience Reports are Collected.

[Vadim Kurdoglov]

Hi Guys!

First if all wanted to say that probably there already is a relevant thread on this topic in the community but I didn't manage to find it. 

So, I will ask my questions here:

1. Do Chrome UX reports show 100% of the users interactions with sites?

2. How to distinguish between user sessions when site resources (CSS, JS, images...) are already cached in users' browsers and when users interact with the site for the first time and the resources are not yet cached? Is there info about collecting data in both scenarios?

3. What is the best way to collect 100% of Real User Metrics on my own (APIs, libraries, tracking scripts) that would give the most exact and precise data.

Thank's in advance)

[Rick Viscomi]

Hi,

Responses inline below.

Rick

On Tuesday, January 12, 2021 at 7:08:13 AM UTC-5 vadim.k...@gmail.com wrote:

Hi Guys!

First if all wanted to say that probably there already is a relevant thread on this topic in the community but I didn't manage to find it. 

So, I will ask my questions here:

1. Do Chrome UX reports show 100% of the users interactions with sites?

Per the CrUX docs, only the experiences "from users who have opted-in to syncing their browsing history, have not set up a Sync passphrase, and have usage statistic reporting enabled" are included in the report. Of those experiences, there isn't any other downsampling.

 

2. How to distinguish between user sessions when site resources (CSS, JS, images...) are already cached in users' browsers and when users interact with the site for the first time and the resources are not yet cached? Is there info about collecting data in both scenarios?

All of these experiences are aggregated together to give a generalized view of the user experience and we don't provide a way to distinguish between cache states. For more granular insights about your users' experiences we recommend collecting and analyzing your own field data. (See 3 below)

 

3. What is the best way to collect 100% of Real User Metrics on my own (APIs, libraries, tracking scripts) that would give the most exact and precise data.

I recommend using the web-vitals.js library along with the RUM vendor of your choosing. That project has some additional info about integrating with Google Analytics, but there are other vendors who either support CWV out of the box, or allow you to report custom metrics like the CWV from the library.

 

Thank's in advance)

[Vadim Kurdoglov]

hi @Rick ,

 Thank's a lot for you feedback!

Regards)