a rather handy little helper is simply called “pv” – pipe view. I mainly use it when copying vms or lots of small files:
tar cf - ./src | pv --timer --rate --average-rate --bytes | ssh machine tar xpf - -C /dst
which then prints something like this:
4.54GiB 0:06:55 [11.2MiB/s] [11.2MiB/s]
pv can also be used to set a rate limit to the transfer using “-L 1m” to restrict the bandwidth to 1 MB/s. For the Mac users out there – homebrew has knows “pv”.