I was looking for proficiency tests and I found this article:
https://www.lingq.com/blog/2015/04/28/language-proficiency-tests/
I thought that it was a good idea to take all 5 tests like that girl did, unlike her I decided that I would take them all in the same language (in English because it's my second language). I'll give you my opinion about all of them.
Bridge (http://www.foreignlanguagetest.com/):
I must say that the one I liked the most is this one, it has listening comprehension unlike the other tests and you are graded by each part individually, so you can see where you must improve. You have 65 minutes to complete this test (I casually had a work emergency while I was doing it so I had to finish it quickly before the time ended), I plan to practice on my grammar (I know I have some issues with some grammar rules I learnt like 20 years ago xD) and take it again soon.
SprachCaffe (https://www.sprachcaffe.com/) and Transparent (https://www.transparent.com/):
They are practically the same test, they divide the test in 4 parts and they grade according to the number of correct answers:
SprachCaffe - 73/80
Transparent - 129/150
Language level test (languagelevel.com):
15 questions in 10 minutes, I'm not sure how they can determine your language proficiency with only 15 questions, but I got the same result as the Bridge test 
Lingq proficiency test (https://www.lingq.com/en/language-proficiency-test/):
This one was easy and fun, like a game, it didn't feel like a test at all. They give you a number of words you "know", I'm not sure how they are supposed to calculate this though.
So, the one I liked the most (Bridge) unfortunately it's only available for Spanish, English and Portuguese. If you know any of these languages I recommend you give them a try with that test, it's worth it. I'll try it later with Spanish just for fun :).
