although I cannot understand the 'problem' as 1Mbps = 1000 or 1024 kbps (depending on provider) you can try www.speedtest.net
Note that 'speedtests' are never a reference and you must run a lot to have an average result.
'Real' tests can be done when downloading a large file or when 'updating' your Ubuntu:
Of course above will be the 'average real download rate' from the mirror server, all routes till your PC, including ALL traffic.
g@KKsep15:~$ sudo apt-get update
[sudo] password for g:
Fetched 10.3MB in 5min 31s (31.0kB/s)
Reading package lists... Done