そろばん屋 · 3 号室
Age Calculator
Calculate exact age in years, months and days.
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How age is calculated
Age is counted the way people normally say it: full calendar years first, then the remaining full months, then the remaining days. Starting from the date of birth, we add whole years while we don't pass the target date, then whole months, and whatever is left is days. If a month is shorter than the birth day (for example someone born on the 31st), the month is treated as complete on its last day.
The totals are exact: total days = (target date − birth date) ÷ 86,400,000 ms, weeks are total days ÷ 7, and total months are years × 12 + months.
What about people born on 29 February?
In non-leap years the birthday is counted as 28 February for the "next birthday" countdown, which matches most legal conventions.
Is my date of birth sent anywhere?
No — the calculation runs in your browser and nothing is stored or uploaded.