Age Calculator
Enter a birth date and optionally a reference date to view age, total days lived, and upcoming birthday details.
Defaults to today for live calculations.
Age Details
Exact age
35 year(s), 10 month(s), 24 day(s)
Reference date: Tuesday, November 25, 2025
Totals
13,112 days • 1,873.14 weeks • 430.79 months
How to Use This Calculator
Choose the birth date
Enter the exact date of birth. The calculator uses calendar math to compute completed years, months, and days.
Adjust the reference date
Leave as today for current age or choose a past/future date to plan milestones or confirm age on a specific day.
Review the insights
See age breakdowns, total days lived, and the countdown to the next birthday with the day of the week.
Formula
Years = Reference Year − Birth Year (adjust for incomplete birthday)
Months = Reference Month − Birth Month (borrow from years if negative)
Days = Reference Day − Birth Day (borrow from months as needed)
Total Days = floor((Reference − Birth) ÷ 86,400,000 ms)
Example: Born 1990-01-01, reference 2025-11-09 → 35 years, 10 months, 8 days • 13,106 days lived.
Age Planning Tips
Accurate age calculations support travel visa applications, retirement planning, student enrollments, and milestone celebrations.
- Use the next-birthday countdown to schedule parties and send reminders.
- Combine with financial planning to align age milestones with savings goals.
- Track medical check-ups based on exact age or months.
- Log multiple family members’ birthdays separately for quick reference.
Frequently Asked Questions
Does it account for leap years?
Yes. Age is calculated using actual calendar days, so leap years are handled automatically.
Can it show age in hours or minutes?
Total days and weeks are provided. Multiply days by 24 or 1,440 for quick conversions if needed.
What if I set a future reference date?
You’ll see how old you will be on that date and how many days until the next birthday after that point.
Can I use this for pets?
Absolutely—birth date math works the same. Combine with species-specific age converters if needed.