The simple version: subtract your birth year from the current year. But there's a catch — you also need to know whether your birthday has passed this year or not.
2026 − 1992 = 34
Birthday (March 15) has passed? YES → don't subtract extra
Age = 34
2026 − 1992 = 34
Birthday (October 5) has passed? NO → subtract 1
Age = 33
When you need exact age — for official documents, medical records, or legal purposes — you count in years, months, and days.
Years: 2026 − 1991 = 35, but birthday hasn't passed → 34 years
Months: From May 20 to April 27 = 11 months back (next month would be May)
Days: April 27 − May 20 = 23 days back from May
Age = 34 years, 11 months, 23 days
Leap years exist because the Earth takes approximately 365.2422 days to orbit the Sun, not exactly 365. To prevent drift in our calendar, we add an extra day every 4 years.
🌍 A year is a leap year if divisible by 4, EXCEPT if divisible by 100 — unless also divisible by 400.
| Year | Leap Year? | Days in February |
|---|---|---|
| 2020 | ✓ Yes (÷4, not ÷100) | 29 |
| 2024 | ✓ Yes (÷4, not ÷100) | 29 |
| 2100 | ✗ No (÷100, not ÷400) | 28 |
| 2000 | ✓ Yes (÷400) | 29 |
| 1900 | ✗ No (÷100, not ÷400) | 28 |
If you were born on February 29, you technically have a birthday only every 4 years. Legally, most countries celebrate your birthday on March 1 in non-leap years.
For precise calculations (like age in hours for medical or legal documentation), you need the exact birth date AND time.
A typical 30-year-old has lived approximately:
💡 Fun fact: By the time you're 30, you've lived roughly 1 billion seconds. At 31.7 years, you've been alive for exactly 1,000,000,000 seconds.
To calculate days until your next birthday from today's date:
August 14, 2026 − April 27, 2026 = 109 days
109 days until your birthday!
Enter your birth date — get years, months, days, hours, and next birthday countdown.
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