Using iperf to test broadband speed

The iperf tool is already widely used by system administrators to test and benchmark networks links. I even used it at home to work out how to layout my powerline adapters for best performance.

A less obvious use for iperf is to measure your broadband speed. Nothing wrong with web based sites like, I use them a lot and can't resist running quick test when I join a new wireless network with my phone.

Maybe you have a headless server, filtered access HTTP access or don't trust the results of a Java app running from inside your browser, then you need to use iperf. Scott from has been kind enough to host a public iperf server. To use this public iperf to get your broadband network speed, see my notes below.

Install the iperf package. On Ubuntu or Debian:

# apt-get install iperf

On Red Hat or CentOS based systems:


# yum install iperf

To run the iperf command

# iperf -c
Client connecting to, TCP port 5001
TCP window size: 22.8 KByte (default)
[  3] local port 60806 connected with port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.1 sec  12.5 MBytes  10.4 Mbits/sec