Use speedtest-cli:

$ curl -s https://raw.githubusercontent.com/sivel/speedtest-cli/master/speedtest.py | python -
Retrieving speedtest.net configuration...
Testing from Comcast Cable (73.1.128.16)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Broadwave (Fort Lauderdale, FL) [43.78 km]: 22.155 ms
Testing download speed................................................................................
Download: 232.72 Mbit/s
Testing upload speed......................................................................................................
Upload: 10.07 Mbit/s