Transition dates are checked at the day level
Reiwa begins on 2019-05-01 and Heisei begins on 1989-01-08, for example. A date outside an era’s actual range is not accepted merely because the year number looks plausible.
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Convert Japanese era dates and Gregorian dates line by line.
Enter one date per line. Example: Reiwa 8-08-29 / 2026-08-29
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Convert Japanese era dates and Gregorian dates line by line. The tool supports Reiwa, Heisei, Showa, Taisho and a limited Meiji range, making it useful when checking dates in Japanese records or documents.
令和6年1月1日 converts to 2024-01-01. In the other direction, 2024-01-01 is displayed in Japanese-era notation as 令和6年1月1日.Era transitions happen on specific dates, not simply on January 1. A transition year can contain two eras, so check the full date. The result is a convenience conversion, not a substitute for an official record.
Reiwa begins on 2019-05-01 and Heisei begins on 1989-01-08, for example. A date outside an era’s actual range is not accepted merely because the year number looks plausible.
Even on the English page, a Gregorian input is converted to Japanese era text such as 令和6年1月1日. This is useful when you need the notation used in Japanese documents.
A year by itself or a year-month value is not enough. The converter also rejects impossible calendar dates rather than silently rolling them into another day.
Earlier Meiji dates are outside this converter’s supported range. That avoids pretending that a simple modern Gregorian mapping covers earlier calendar usage.
The input order is preserved, and an unconvertible line remains visible with an error message, which makes mixed lists easier to review.
Related references: ISO 8601 · Date formats · World calendars