# How did Japanese obtain a unit of measure called a カップ that's 200 mL?

I've encountered a measuring cup which has units of カップ, 水mℓ (水ml), 米[unknown kanji]g and [three unknown kanji]g. 1 カップ corresponds exactly to 200 水mℓ.

According to Wikipedia, there's a Japanese cup that corresponds to 200 ml. By contrast, the US customary cup is approximately 237 mL, and an imperial cup (as in the British empire) is 284 millilitres.

How did Japanese obtain a unit of measure called a カップ which corresponds to neither the British or US unit of measurement?

This post on cooking.SE is about 合, which is 180 mL.

• I have no idea, but perhaps you could try to find out if 200 ml is the universal equivalent for カップ in Japan, and when it was introduced. In Sweden, a kopp (コップ) is traditionally somewhere around 150~200 ml (though 250 ml is expected in some more modern recipies), I guess ”elsewhere” had this natural variation as well, as you use/used the actual cups at hand... – Kess Vargavind Feb 20 '17 at 7:58

In Japanese recipe books, 1カップ is 200 mL, 大さじ1杯 ("large spoon") is 15 mL, 小さじ1杯 ("small spoon") is 5 mL. Aya Kagawa, a Japanese nutritionist, defined it in 1948.

The metric cup is `250mL`, which is exactly `1/4 of a Litre`, so I'd imagine they just decided to define a cup as `1/5 of a Litre` instead.

This could be to make it closer to the `Gou` unit, which is `180mL`, or perhaps it's a more appropriate serving size for Japanese beverages.

• Well intentioned speculation isn't very helpful. – Andrew Grimm Feb 20 '17 at 7:41