When filling in the year on a document or checking a date of birth, it is common to wonder "what Gregorian year is Reiwa 6?" Converting between wareki (Japanese era years) and Gregorian years is easy: once you know the starting year of each era, it comes down to simple subtraction. This article lays out a quick-reference table and formulas for Reiwa, Heisei, Showa, Taisho and Meiji, along with how to handle era-change years.
1. Quick-reference table of era start dates
The start dates of the major eras and their reference points against the Gregorian calendar are as follows.
| Era | Start date | Gregorian year of year 1 | Gregorian → era year formula |
|---|---|---|---|
| Reiwa (令和) | 1 May 2019 | 2019 | Gregorian − 2018 |
| Heisei (平成) | 8 January 1989 | 1989 | Gregorian − 1988 |
| Showa (昭和) | 25 December 1926 | 1926 | Gregorian − 1925 |
| Taisho (大正) | 30 July 1912 | 1912 | Gregorian − 1911 |
| Meiji (明治) | 25 January 1868 | 1868 | Gregorian − 1867 |
2. Converting from Gregorian to wareki
When you know the Gregorian year, look at which era's range that year falls into and apply the formula from the quick-reference table. For example, 2024 falls within Reiwa, so 2024 − 2018 = Reiwa 6. The year 2000 falls within Heisei, so 2000 − 1988 = Heisei 12.
The thing to watch for is years in which the era changed. Calculating with the formula alone makes it easy to get the boundary wrong, so keep in mind the concept of "year 1" and the era-change date covered in the next section.
3. Converting from wareki to Gregorian
The reverse direction is addition. Using each era's "Gregorian year of year 1" as the base, you find it with Gregorian year of year 1 + era year − 1. For Reiwa that is 2019 + era year − 1 = 2018 + era year. Reiwa 6 is 2018 + 6 = 2024, and Heisei 12 is 1988 + 12 = 2000.
4. Notes on "year 1" and era-change years
The first year in which an era began is called gannen (year 1), which corresponds to the number 1. Reiwa 1 is 2019. Because eras change partway through the year, a Gregorian year in which an era changed has two era names side by side.
- 2019: up to 30 April is Heisei 31, and from 1 May onward is Reiwa 1.
- 1989: up to 7 January is Showa 64, and from 8 January onward is Heisei 1.
- 1926: up to 24 December is Taisho 15, and from 25 December onward is Showa 1.
For this reason, a boundary year cannot be pinned to a single era from "the Gregorian year alone." Once you know the date, the era is determined.
5. A method you can try yourself (simple calculation)
You can also check with a calculator or a console. Just getting Reiwa from a Gregorian year takes a single subtraction.
// Gregorian → Reiwa (approximation, assuming the date does not cross an era-change day)
const seireki = 2024;
console.log("Reiwa " + (seireki - 2018)); // Reiwa 6
// Wareki → Gregorian
const reiwa = 6;
console.log((2018 + reiwa)); // 2024If you want to correctly judge dates that cross an era-change day, or convert Heisei and Showa all at once, enter the date into the conversion tool below. It judges the boundary at the level of individual dates.
Free Tool Check it with the Wareki / Gregorian Conversion Tool Enter a Gregorian date to see the wareki, or enter an era and year to see the Gregorian year. It judges boundaries that cross an era-change day correctly, and everything runs entirely in your browser.Frequently Asked Questions (FAQ)
How do I convert a Reiwa year to a Gregorian year?
Add 2018 to the Reiwa year number to get the Gregorian year. This works because Reiwa began on 1 May 2019, so Reiwa 1 corresponds to 2019. For example, Reiwa 6 is 2018 + 6 = 2024. To go the other way and find the Reiwa year from a Gregorian year, subtract 2018 from the Gregorian year.
What are the formulas for Heisei and Showa Gregorian years?
For Heisei use "Gregorian − 1988" and for Showa use "Gregorian − 1925" to find the era year number. For example, the year 2000 is 2000 − 1988 = Heisei 12, and 1980 is 1980 − 1925 = Showa 55. However, in years when the era changed, the era depends on the month and day, so for boundary years you also need to check the date.
Why does the same Gregorian year sometimes have two era names?
When an era changes partway through the year, that year contains both the old era and the new era. For example, in 2019 the period up to 30 April was Heisei 31, and from 1 May onward it was Reiwa 1. Once you know the exact date, the era is uniquely determined.