Command line speedtest tools

Today I’m sharing three tools for checking your internet and LAN speed: speedtest, fast and iperf.


speedtest is an old favourite. It’s implemented in Python, packaged in apt and also available with pip. You can use it as a command line tool, or within a Python script.

Install it with:

sudo apt install speedtest-cli


sudo pip3 install speedtest-cli

Then run with the command speedtest:

You’ll see your download and upload internet speeds.


fast is a service provided by Netflix, its web interface is at and it has a command line interface available as a snap (for Ubuntu):

sudo snap install fast

There’s another implementation that’s done in node, so you can install that with npm instead, on any other system:

sudo npm install fast-cli

Both provide the same basic interface: just type fast and hit enter:

You’ll see your internet download speed. The version that’s in the snap store doesn’t seem to support getting your upload speed, but the npm one does, via the -u flag.


iperf is a great way to test your LAN speed, rather than your internet speed. Debian, Raspbian and Ubuntu users can install it with apt:

sudo apt install iperf

It’s also available for Mac and Windows.

Once it’s installed, you’ll need two machines on the same network (both with iperf installed). Designate one as the server and run:

iperf -s

That will wait for incoming connections from clients. Use another machine as a client, and run:

iperf -c

using the IP address of the server.

It only takes a few seconds to do a test, and it’ll come back with the transfer size and calculated bandwidth. I ran a few tests from my PC and my laptop, using my home server as the server. I recently put in Cat6 ethernet around my house so I get up to 1Gbps speeds from my wired connections, but a much lower speed on WiFi connections:

You may also notice a recorded 16Gbps! That was me testing using the server to test itself, so it’s just testing how fast it can write to its own disk. The server has HDDs, so it’s only 16Gbps, but my desktop PC gets 46Gbps and my (newer) laptop gets over 60Gbps as they have SSDs!