How to Calculate Your Exact Age
Your age in years is simply the difference between the current year and your birth year, minus one if your birthday hasn't occurred yet this year. But calculating exact age in months and days requires accounting for varying month lengths and leap years.
The RoughTools Age Calculator handles all of this automatically — just enter your birthday and get your exact age in years, months, days, hours, minutes, and seconds.
Important Age Milestones
| Age | Milestone (US) | |---|---| | 13 | Teenager, social media age of consent (COPPA) | | 16 | Driving age (most US states) | | 18 | Legal adult, vote, join military | | 21 | Legal drinking age (US) | | 25 | Car rental without surcharge, brain fully developed | | 59½ | IRA withdrawals without penalty | | 62 | Earliest Social Security eligibility | | 65 | Medicare eligibility, full retirement for some | | 67 | Full Social Security retirement age (born 1960+) |
What Is a Leap Year?
A leap year has 366 days instead of 365, with February 29 added. Leap years occur every 4 years, except for years divisible by 100 (not leap years), except for years divisible by 400 (are leap years). So 2000 was a leap year; 1900 was not.
If you were born on February 29, most countries celebrate your birthday on either February 28 or March 1 in non-leap years. Legally, most jurisdictions treat March 1 as your birthday in non-leap years.
How Old Are You in Different Units?
A 30-year-old person has lived approximately:
- 360 months
- 1,565 weeks
- 10,958 days (including ~8 leap years)
- 262,992 hours
- 15,779,520 minutes
Use the age calculator to find your exact values, including a live countdown to your next birthday.