How is read time calculated?

[wire]

I just wonder how this is calculated? Do you use a cookie cutter word per minute of a human calculation? Time spent on site? If that is the case, what happens if a user idles?

[dax (Daniela)]

Here the technical details:

How does post tracking work in Discourse

Discourse tracks read time for every post users see on the screen. This system has evolved over the years and I find I often need to refer back to the code to figure out how this works and why it exists. This post covers the painful technical details of the current implementation. How the Discourse client tracks timing Post timing tracking is implemented in screen-track.js.es6. This module is responsible for tracking how long a post has been on the screen and how long the topic has been on scr…