[sascha_sl]

speedtest.net used to have a sibling "pingtest" site that measured your jitter. I'm not sure why they don't exist anymore.

[Nextgrid]

I remember it using a Java applet. I think the reason none of the online test sites support it is because it’s hard to test latency & jitter in the browser as the lower layers try hard to compensate for it.

[sascha_sl]

Oh. It was Flash.

Sometimes I forget that was ever a thing!

[fomine3]

Speedtest for random server (servers listed on Ookla is quite random) is useful but ping for random server is a bit useless. Just ping for targeted server that runs service you use.