This seems to be a pretty popular quiz right now. I thought that it was a fair test:

http://www.arealme.com/vocabulary-size-test/en/

I got a score of 23100, but I don't know what it means. Vocabulary skills good, math skills bad?

Yeah, there was another smaller number. 4 point something %. I forget the exact number.

I got 22650 (top 6%)

22222

★★★ Top 6.30%

Your vocabulary is at the level of professional white-collars in the US!