Engagement time

Mrkr measures how long a page stays visible and how long the visitor is actively engaged. Hidden tabs and idle time are kept separate from active attention.

#Engaged time

Engaged time only accumulates while the tab is visible and the visitor has interacted (mouse movement, a key press, a scroll, a click, or a touch) within the last 30 seconds. A tab left open and idle, or backgrounded, stops accumulating engaged time until activity resumes, so a tab left open overnight doesn't inflate a page's average time-on-page. Each page's totals are capped at 30 minutes, the same window that ends an idle session.

Three numbers are reported together, per page, on a page_leave event: wall-clock duration, visible time, and engaged time. They are cumulative totals rather than increments, and the same page can report more than once (when the tab is backgrounded, then again when it is finally closed). The server keeps the maximum it has seen, so a repeated report is harmless and a lost final beacon still leaves the last good reading in place. A report whose numbers haven't moved by a whole second since the previous one is skipped.