Simple as that Title.
I have used Speedtest.net in the past, but it’s way commercialized now. I’m looking for this for a friend that had a geek for hire at her house, and she was asking me questions on what to do while he was there. 
Told her to do make sure he does the basics, and that he should have a laptop to connect to her wireless to compare speeds between the two computers in case her laptop was messed up. Perhaps her net provider has fallen on it’s face. Don’t know.
Commercialized? As in they have ads? Just block them with ublock origin and then it won’t really matter which speed test you use, they’re all similar.
Otherwise here’s two random ones that work well enough:
One suggestion is to find out if her ISP has a speed tester.
I had an issue not too long ago, and the technician who came out used the ISP’s (RCN) speed tester when he was checking my connection. He recommended I continue using that, as the speed check is then logged by RCN, so if I’m having an issue there’s a hard record of it. So I have that bookmarked now and will use it if I have an issue again.
It was a provider issue, btw, the outside connection to the whole building was eroding. They had it fixed under 48 hours.
I’ve been using DSLreports.com for some time.