Speaker clock

[thies]

Is it possible to set up a speaker clock on Zoom? So that the speaker knows how much longer he is allowed to speak.

[bstrelko]

At this time, Zoom's integrated timer can be configured based on the meeting's scheduled duration or time elapsed.

You can investigate 3rd party timers (as well as Zoom's Timer app) that might better fit your purpose at the Zoom Marketplace (https://marketplace.zoom.us/).