Calculate your exact age in years, months, days and more — instantly, free, no signup
An age calculator is a tool that determines someone's exact age based on their date of birth and a reference date (usually today). While most people know their age in years, calculating exact age in years + months + days requires careful handling of varying month lengths, leap years, and date arithmetic. The FileTools Age Calculator does all this automatically and provides six metrics at once: complete years, additional months, additional days, total days lived, total hours, and total minutes. It also shows your next birthday countdown — handy for planning celebrations or noting how many days remain. The calculator works entirely in your browser, so your date of birth and any other dates you enter stay completely private.
Common use cases: filling out government, medical, or school forms requiring exact age in years and months; verifying eligibility for retirement benefits, voting, driving, or alcohol; computing how old your child is in months for pediatric milestones and vaccination schedules; calculating age difference between siblings, partners, or relatives; figuring out how old you'll be on a future date or anniversary; determining how long ago a significant event happened; calculating someone's age at the time of a historical event; planning birthday parties with an accurate days-until countdown; and satisfying curiosity about exactly how many days, hours, or minutes you've been alive.
Years: complete years between birth date and target date.
Months: additional months beyond complete years (0-11).
Days: additional days beyond months (0-30).
Total Days: total number of days lived between the two dates — accounts for all leap years.
Hours: total hours lived (Total Days × 24).
Minutes: total minutes lived (Total Hours × 60).
Plus a bonus: countdown until your next birthday, including the exact date.
The calculator uses JavaScript's native Date object, which correctly accounts for: leap years (every 4 years, except century years not divisible by 400); varying month lengths (28, 29, 30, or 31 days); month boundaries when calculating exact age; and timezone-neutral date math. February 29 birthdays are handled accurately — for non-leap years, the next birthday displays as March 1. Total days lived reflects every actual day on the calendar between the two dates.
1. Enter your date of birth in the first field
2. The "Age at Date" defaults to today — change it to any past or future date if needed
3. Click "Calculate Age"
4. View your exact age across six metrics: years/months/days, total days, hours, and minutes
5. Below the results, see the days remaining until your next birthday and the exact date
✅ 100% free — no signup, no ads in tool, no tracking
✅ Six metrics in one calculation
✅ Next birthday countdown included
✅ Calculate age at any past or future date
✅ Handles leap years and February 29 correctly
✅ Client-side only — your date of birth never leaves your device
✅ Works on Windows, Mac, Linux, Android, iOS — any browser
Enter your date of birth in the first field and the target date (today by default) in the second field, then click Calculate Age. The tool shows your exact age in years, months, and days, plus total days, hours, and minutes lived. It also shows when your next birthday will be.
The calculator uses JavaScript's native Date object which automatically handles leap years, varying month lengths (28-31 days), and timezone differences. February 29 birthdays are calculated correctly — your exact age in days will reflect the actual number of days lived, including all leap day transitions.
Yes. The Age at Date field defaults to today, but you can change it to any date — past or future. This lets you calculate how old someone was at a specific event (a wedding, graduation), how old you'll be on a future date, or the exact difference between any two dates.
No. All calculations happen entirely in your browser using JavaScript. Your date of birth and any other dates you enter never leave your device — nothing is uploaded, logged, or stored. The tool works offline once the page is loaded.
Common uses include: filling out forms that require exact age, calculating eligibility for school admission or retirement, planning birthday celebrations, computing age differences between family members, determining how long ago an event happened, calculating your child's exact age in months for pediatric reference, or simply finding out how many days you've been alive for fun.
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