Those are all M-Lab tests - Stadia and google search results. They're not always certainly through Google's network (I would have to imagine they're typically not).
Once upon a time, Robert Webb <rwfireguru@gmail.com> said:
> None of them are accurate. The one from a Google search gave me around
> 280Mbps, the stadia gave me 39Mbps, and Ookla gave me close to 500Mbps..
Browser-based speed testing is a crapshoot for anything above about
100M... Ookla has a native client for just about every client OS that
tends to be much more accurate.
--
Chris Adams <cma@cmadams.net>