Iperf has been around for over 25 years.
This is a lightweight and easy to use network speed tester. There are clients and servers for both Linux and Windows. When installing for Debian based systems like Ubuntu, just make sure to apt install iperf3 and you are good to go.
During installation it will offer to run as a daemon which is quite convenient.
The default listening port is 5201
Once you have the Server up and running, just call it with the “client” with the command iperf -c “servername”
Couldn’t be simper and gives you the measures and stats.
There are also several pubilc iperf servers, listed here https://iperf.fr/iperf-servers.php
