Japanese Longevity Milestones Calculator
Enter a birthdate to instantly calculate the year (Western and Japanese era) of each traditional Japanese longevity celebration: Kanreki (60), Koki (70), Kiju (77), Sanju (80), Beiju (88), Sotsuju (90) and Hakuju (99).
What the longevity celebration calculator does
Enter a date of birth once and this calculator lists the target years for the seven main Japanese longevity celebrations, from Kanreki at 60 through to Hakuju at 99, each with the Gregorian year, the Japanese era year and where it stands relative to today (past, this year, or still to come). It spares you counting birthday by birthday and gives you the whole set in a form you can drop straight into a family calendar.
Longevity celebrations are traditional Japanese milestones, each with its own origin — some, like Kanreki, mark the point where the zodiac cycle comes full circle, while others come from the shape or reading of a Chinese character. This tool calculates by adding the celebration age directly to the year of birth, the full-age method, so in regions and families that celebrate by the traditional counted age the target year may fall a year either side.
How to use the longevity celebration calculator
- Enter the date of birth Pick the date of birth of the person being celebrated from the calendar, or type it in directly.
- Look over the list of celebrations As soon as you enter it, all seven from Kanreki to Hakuju line up in the table automatically. There is no calculate button to press.
- Check the target year and the era year Each row shows the Gregorian target year alongside the Japanese era notation, so you can confirm the plan in whichever calendar you use.
- Spot the nearest celebration by its badge Rows carrying the "this year" badge are highlighted, so the celebration that needs preparing soonest stands out at a glance.
Tips for getting more out of it
- Kanreki marks the completion of a 60-year cycle of the Chinese zodiac and the ten celestial stems, returning to the same sign you were born under. Gifting a red vest and hood symbolizes a symbolic "rebirth" as a baby.
- Koki takes its name from a line by the Tang-dynasty Chinese poet Du Fu: "living to seventy has been rare since antiquity."
- Beiju is named because the character for "rice" (米) can be broken down into strokes resembling "eighty-eight," while Sanju comes from a cursive form of the character for "umbrella" (傘) that resembles "eighty."
- The target year for each milestone can be calculated using either the traditional Japanese "kazoe-doshi" age (counting the birth year as age one) or the modern Western age, depending on the region or family. This tool uses the Western-age convention (birth year + milestone age).
When the longevity celebration calculator helps
Arranging the date of a celebration early
Put the year in your calendar as soon as you see it marked as still to come, and you have room to settle on a date the whole family can make.
Not missing the moment for a gift to parents or grandparents
Knowing milestone ages such as Kanreki or Koki well in advance makes it easier to be ready in time for preparing a gift or finding a venue that needs booking.
Taking in several people's celebrations at once
Enter the dates of birth of parents and relatives one after another and you can list everyone's nearest celebration in a short space of time.
Writing documents and invitations in the Japanese era
Even when you want the Japanese era on an invitation or a commemorative gift, seeing it lined up against the Gregorian year prevents mistakes in the notation.
Longevity celebration terms
- Kanreki (還暦)
- The celebration at 60. The name comes from the sexagenary cycle — the combination of the twelve zodiac signs and the ten heavenly stems — coming full circle in 60 years and returning to the sign of the year you were born.
- Koki (古希)
- The celebration at 70. The name comes from a line by the Tang dynasty Chinese poet Du Fu: that living to seventy has been rare since ancient times.
- Kiju (喜寿)
- The celebration at 77. The cursive form of the character 喜 looks like 七十七, seventy-seven, and so was assigned to the celebration at this age.
- Sanju (傘寿)
- The celebration at 80. It comes from the abbreviated form of 傘 looking like the characters 八十, eighty, combined.
- Beiju (米寿)
- The celebration at 88. It was named after the fact that breaking the character 米 apart gives the shapes 八, 十 and 八 — eighty-eight.
- Sotsuju (卒寿)
- The celebration at 90. It comes from the abbreviated form of 卒 looking like 九十, ninety.
- Hakuju (白寿)
- The celebration at 99. Take the top stroke off the character 百, a hundred, and it becomes 白 — which stands for a hundred minus one, ninety-nine.
- Counted age
- The traditional way of counting age that treats the year of birth as one year old and adds a year at each New Year's Day thereafter. The target year may fall a year either side of the full-age method this tool uses.
Frequently asked questions
Side Note — the colors and origins of Japanese longevity celebrations
Each Japanese longevity milestone traditionally has an associated color. Kanreki is red, Koki, Kiju and Sanju are purple, Beiju is gold or yellow, Sotsuju is white or purple, and Hakuju is white — the color shifting as the milestones progress. Each color is said to carry meaning tied to warding off misfortune or symbolizing nobility.
Many of these names are tied to Chinese character wordplay. Kiju comes from the cursive form of the character for "joy" (喜) resembling the numbers "seventy-seven," while Sotsuju comes from an abbreviated form of the character for "graduate" (卒) resembling "ninety" — a distinctive feature of how these names emerged from the visual shapes of kanji.
The custom of celebrating longevity milestones is said to date back to the Heian period, when people held a "celebration of blessing" (ga no iwai) every ten years starting at age 40. The specific names used today — Kanreki, Koki, Kiju and so on — are believed to have become firmly established sometime after the Edo period.