Does Zoom always use native resolution for Screen Sharing or is there a limit?

Solution 1:

You can share your entire screen, in which case it will share the whole 3000x2000 and scale it down to whatever resolution their streaming at, which is usually lower, like 1920x1080 etc.

You can also choose to share one application. If you resize that application to a fraction of your screen, the chance is a lot higher that they will be able to read it.

Another option is to temporarily reduce your own resolution to a lower one.

Solution 2:

According to Zoom help center link @Tetsujin posted (thanks to him), the Zoom Screen Sharing will always be at the full native resolution:

Group HD

...

For the time being, standard video, not HD video, will be activated when 3 or more participants join a group meeting. HD video (720p) will be activated for 2 participants or when a Zoom Room or Conference Room Connector joins a group meeting. HD video (1080p) will only be activated for selective use cases such as large format broadcast events.

...

Screen sharing is not affected by Group HD. Screen sharing will display content at the native resolution of the desktop, application, or portion of the screen being shared.

So in my case, it should be the full 3000x2000 when sharing full screen.