Free Online Age Calculator

Enter your date of birth in the date picker above. The calculator subtracts your birth date from today's date, accounting for varying month lengths and leap years, to give your exact age in years, months, and days.

Enter your birthday and check the unit breakdown section. It shows your total age in days, weeks, months, and hours. For example, a person born on January 1, 1990 is approximately 13,224 days old as of March 2026.

Use the "Calculate to" field to set a custom end date instead of today. The calculator shows the exact difference in years, months, and days between your birth date and any target date, past or future.

Yes. The calculator uses calendar-accurate date math. If you were born on February 29, your age is calculated correctly — your birthday falls on February 28 in non-leap years for the countdown calculation.

A standard year has 52 weeks and 1 day (52.143 weeks). A leap year has 52 weeks and 2 days. The age calculator shows your total lived weeks accounting for all leap years since your birth.

Chronological age is the time elapsed since birth — what this calculator measures. Biological age estimates how old your body is based on health markers like fitness and cellular aging. They can differ significantly.

In most jurisdictions, you legally turn a given age at the start of your birthday. Some countries use different systems — in Korean age, you are 1 at birth and gain a year every January 1. This calculator uses the international standard.

The birthday countdown shows the exact number of days until your next birthday and the date it falls on. It updates automatically based on today's date.