speedometer: How to check Internet Speed via Terminal?

To check server current Internet speed, not the max speed in terminal/command line, the easiest way is speedometer. Take Ubuntu as example:

Install:
$ sudo apt install speedometer

Usage:

$ speedometer -rx eth0

unit conversion:

bit=bit

B=byte

1 byte=8 bit

bps=bit/s

MB/S = megabyte per second

MiB/s = mebibyte per second

1 meibyte=2**20=1048576 bytes = 1024 kibibytes

1 Mbps=1 Mbit/s = 0.125MB/s =(0.125M/2**20)= 0.1192 MiB/s