Now I don't usually give away business ideas but I've got so many lately and this one's so fringe that what the heck. If someone does it before me, I'll pay 2 bucks to test it. So with the LLMs and shit lately, I trust they are able to make a statistics of words used in a language. You can then use that to estimate how many words someone speaks. Problem is the only site I know so far that estimates that is "Test Your Vocabulary" here, and only does it for English: https://preply.com/en/learn/english/test-your-vocab But I would be curious of other things. Like, how many words do I speak in German. Or how many words does an ethnic Hungarian that lives in Romania speaks in Romanian. I'm actually quite curious of that since there seems to be two types of ethnic speakers. There are those who learned the foreign language in childhood along their native language and when I talk to them I feel totally comfortable to use my full =~ 35,000 words vocabulary. And then there's those who basically learned it as a foreign language and they certainly understand me but subtle jokes and nuances are lost. So I wonder how many words in general one has to speak in a foreign language to qualify as comfortable speaking anything with the natives. Would people pay 2 bucks (in total advertise revenue over showing them crap while taking the test)? Maybe, dunno. Times 100 million people taking the test that's not so bad. If anyone wants to make it, go ahead. Otherwise I might do it but it's low on priority list after bugs, deadlines and other startup ideas.