Any sites I've come across seem to have dubious credentials.
I did the Mensa test years ago - IQ 148. I could have joined but thought the whole idea was silly - I was just curious.
Career wise, I'm doing "OK". A guy I went to school with was fairly academically challenged - borderline special needs I would have said: he now runs a successful business.
Charm, trust, resourcefulness and of course hard work, can often serve you better than IQ. I want to hang onto mine of course, but I think it's overrated.