
With this easy hack you’ll never be confused by the Japanese calendar ever again!
There are a lot of differences between Japan and the Western world, and one of those differences is the way they refer to years on the calendar.
While the current year is 2022, according to the Western calendar, here in Japan it’s also known as Reiwa 4. This is due to the centuries-old tradition of tying an era to the reigning monarch, and seeing as Emperor Emeritus Akihito stepped down from the throne and handed the role over to his eldest son, Emperor Naruhito four years ago, a new era began, and it was officially named Reiwa.
This changeover brought an end to the 30-year long Heisei era, and caused a bit of confusion for official documents like driver’s licenses made before the Reiwa era, which had expiry dates still listed in Heisei years.
▼ Case in point: our reporter P.K. Sanjun’s driver’s license, which is set to expire on 10 February in Heisei 35, despite Heisei 30 being the last year of the Heisei era.
With some documents still going by Heisei, others by Reiwa, and others by the Gregorian calendar, converting dates can take a lot of time and effort in Japan. Even P.K. has to go into math meme mode every time he needs to work out his license renewal date, furrowing his brow and placing his fingers on his temples as he murmurs “Heisei 35…Reiwa 5…2023” while math equations dance over his face.
This mental strain got our reporter thinking that there had to be an easier way to convert the Gregorian calendar to Japanese years, and when he asked his Japanese readers about it, one of them came up with an idea so great he decided to share it with all of us.
The calculation formula for converting the Christian era to Reiwa is…
▼ …to add the last two numbers of the Western year!
Sure enough, this surprisingly simple method works — for this year, two plus two is four (Reiwa 4), and for next year, two plus three is five (Reiwa 5). It does have its limitations, though, because when you get up to 2030, the calculation falls flat, as three plus zero is three, but the Reiwa year for 2030 would be Reiwa 12.
▼ Still, that gives us a whole seven years, from now until 2029, to use the add-the-last-two-numbers method.
For those with better math skills than P.K., there is a fail-proof method you can use throughout the Reiwa era, and it involves subtracting 18 from the last two digits of the Gregorian calendar.
Using that method, the year 2030, 30 minus 18, will be Reiwa 12, and so on, giving you an accurate method for converting Gregorian to Reiwa for the rest of the era, however long that might be. And if you ever need to convert Reiwa to the Gregorian calendar, all you have to do is add 18, which will give you the last two digits of the Gregorian calendar.
For someone like P.K., though, who takes ages to make calculations, the single-digit calculation method is just enough math for him to handle, and it’ll serve him well as his go-to method for the next seven years.
After that, he’ll have to get used to adding and subtracting double-digit numbers, but for now, he’s happy to live in “beautiful harmony” with a more simple approach, in true accordance with the meaning and ideals of Reiwa.
Images © SoraNews24
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[ Read in Japanese ]




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