Hmm Japan uses both 50hz and 60hz.

Saw them discuss this on NHK in relation to the current power loss in Japan and it seems west uses 60hz and the east uses 50hz , weird!.

"In Japan, the western part of the country (Kyoto and west) uses 60 Hz and the eastern part (Tokyo and east) uses 50 Hz. This originates in the first purchases of generators from AEG in 1895, installed for Tokyo, and General Electric in 1896, installed in Osaka. The boundary between the two regions contains four back-to-back HVDC substations which convert the frequency; these are Shin Shinano, Sakuma Dam, Minami-Fukumitsu, and the Higashi-Shimizu Frequency Converter."

But Japan sticks to 100 volt while some other countries go all the way from 100v50hz to 240v60hz.