How to Calculate Your Age from a Birth Date
Age = current year - birth year, minus 1 if this year's birthday hasn't happened yet. Born 1990-08-15, on today's date 2026-05-29: 2026-1990 = 36, but the August birthday hasn't come, so age = 35.
Open the interactive Everyday Lifestyle tool →Formula: age = year_now - year_born (- 1 if birthday not yet passed)
Key facts
| Formula | age = year_now - year_born (- 1 if birthday not yet passed) |
|---|---|
| Reference date | 2026-05-29 |
| Example born | 1990-08-15 -> age 35 |
| Born 1990-01-10 | age 36 (birthday already passed) |
Frequently asked questions
How do I count age if my birthday is later this year?
Subtract one. If born 1990-08-15 and today is 2026-05-29, the birthday hasn't arrived, so you are 35, not 36.
What age is someone born in 2000?
As of 2026, 26 if their birthday has passed this year, otherwise 25 (26 - 1).
How is age calculated in Japan?
Same arithmetic (man-nenrei). Note legal age changes at the day before the birthday under Japanese age law.
Related pages
Age Calculator is part of Everyday Lifestyle on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.
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