Age Calculator
Enter a birth date and either another date or 'today' to calculate exact age including years, months, and days.
Age = end_date - start_date, broken down into years, months, and days using calendar logic (variable month lengths, leap years).
How Age Is Calculated
The calculator uses precise calendar logic to determine age:
1. **Years**: Full years between the two dates. 2. **Months**: Remaining months after full years are accounted for. 3. **Days**: Remaining days after full months are accounted for.
**Example**: Born on March 15, 2000. Age as of October 28, 2026: - Years: 26 (from March 2000 to March 2026) - Months: 7 (from March 15 to October 15) - Days: 13 (from October 15 to October 28)
Result: 26 years, 7 months, 13 days.
**Leap year consideration**: February 29 birthdays are typically treated as March 1 for age calculation in non-leap years, though policies vary by jurisdiction.
**Variable month lengths**: The calculator accounts for months with 28, 30, or 31 days, so March 31 → April 30 is 1 month, not varying by month.
Age Calculator Results Explained
The output format is: **YY years, MM months, DD days**
- **Years**: Complete solar years between the dates - **Months**: Complete calendar months after the years - **Days**: Remaining days after the months
**Example uses**: - Meeting someone new: "How old are you?" → "26 years, 7 months" - Retirement planning: Tracking exact service years - Legal milestones: Voting age (18), drinking age (varies), retirement (65/67) - Health: Tracking exact age for medical forms, insurance - Life events: Anniversaries, birthdays planning
**Why precision matters**: Two people both "26 years old" may actually be 26 years 0 months and 26 years 11 days - a significant difference for legal, health, and retirement contexts.
Special Date Scenarios
- **Future dates**: Calculate age on a future date (e.g., "How old will I be on my 50th wedding anniversary?") - **Past dates**: Calculate age as of a historical date (e.g., "How old was my grandfather on D-Day?") - **Same-date difference**: Enter same start and end date → 0 years, 0 months, 0 days - **Leap year birth**: February 29 → calculator uses February 28 or March 1 depending on convention
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Open calculator →Frequently Asked Questions
How does the calculator handle leap years?
The calculator uses standard calendar rules. Someone born on February 28 will have their age advance on February 28 every year. Someone born on February 29 in a leap year: in non-leap years, the anniversary is typically observed on February 28 or March 1, depending on local convention.
Can I calculate age between two historical dates?
Yes. Enter any start and end date - the calculator will compute the exact difference in years, months, and days, accounting for all calendar rules including leap years and variable month lengths.
Is the age result the same worldwide?
The mathematical calculation is the same, but legal age thresholds (voting, drinking, retirement) vary by country. The calculator provides the exact time difference regardless of location.
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