https://web.archive.org/web/20021206055155/http://alllooksam...
Sep 14, 2001 it was taken out of beta.
I remember taking it as a freshman in college and getting well above random chance. 60–70% correct? A year later I took it with my sophomore roommate, from China. Again, 2/3-ish correct. He scored about random chance from what I recall.
I've always thought you could tell. Not 100% of the time; there's plenty of genetic mixing, Japanese people and Koreans share somewhat recent genetic history, Korea and China border each other, China is a ton of different ethnicities, etc. But certainly better than random chance if you've been around enough East Asians in your life.
I agree with a descendant above who said fashion is really useful. That's super true. I used to joke at uni that an East Asian wearing pastels was invariably Korean (this is very much NOT the case in SK these days). Japanese have had very distinct youth fashions for twenty years, as I lived there and witnessed them, and nowadays I can be across the playground with my kids and see a woman and immediately know by what she's wearing that she's from Japan.
China, being enormous, is a mixed bag.
That being said, there's facial structure stuff. It's kind of hard to put into words. It's a vibe you get. There's a university (Penn State or something?) that has a professor who puts his huge survey sociology class online. He talks about this, that early and constant exposure to some group(s) makes you better, for the rest of your life, and recognizing them. Has to do with attractiveness, too.
He brings white girls up to pick which Asian guy is the most attractive, and you can tell they really struggle to articulate it. But he brings Asian girls up and say exactly which one and explain why from his clothes, his facial features, etc.
It really is like if you aren't around (in this case) Asian people growing up, you have a kind of facial blindness where they alldolooksame.