Overview

I had the opportunity to convert Japanese calendar dates (wareki) to the Western calendar using the calendar conversion service of HuTime, a temporal information analysis software, so this is a personal note for future reference.

https://www.hutime.jp/

Conversion Example

Enter a Japanese calendar date in the {wareki date} placeholder below.

https://ap.hutime.org/cal/?method=conv&ical=1001.1&itype=date&ival={wareki date}&ocal=101.1&oform=yyyy-MM-dd&out=json

For example, for “Keio 4, September 8” (慶応4年9月8日), the URL is as follows.

https://ap.hutime.org/cal/?method=conv&ical=1001.1&itype=date&ival=慶応4年9月8日&ocal=101.1&oform=yyyy-MM-dd&out=json

Other Usage

Detailed explanations are available at the following link. Please refer to it for parameter specification methods, etc.

https://ap.hutime.org/cal/

Summary

I hope this serves as a useful reference for using the HuTime Web API.

I also extend my gratitude to the developers of HuTime for creating such a valuable tool.