Age Calculator
Use this age calculator to find your exact age from your date of birth in years, months and days. It also shows the total number of days lived and the number of days until your next birthday. This is useful for personal curiosity, forms, school registrations, health records and any situation where you need a precise age rather than just the birth year.
Frequently Asked Questions
The calculator subtracts the birth date from today's date and extracts full years, remaining months, and remaining days. It accounts for varying month lengths (28–31 days) and leap years for precision.
If today is your birthday, remaining months and days will be 0, and "days until next birthday" will show 365 (or 366 in a leap year) as the next occurrence is exactly one year away.
Yes. Leap-year birthdays are still handled as calendar dates, though legal or administrative conventions for celebrating them can vary by country.
How this calculator works
Formula explanation
**Method:** Subtract birth date from today → extract full years, remaining months, remaining days | Total days = (today − birth date) in milliseconds / 86,400,000 | Next birthday = nearest future occurrence of birth month/day.
Worked example
**Example:** Born on January 1, 1990, today is March 21, 2026 → Age: 36 years, 2 months, 20 days | Total days: ~13,224 | Days until next birthday: ~286.
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