Age in Years, Months, Weeks, Days, Hours
Convert any birth date into your exact age expressed across years, months, weeks, days, hours and minutes.
Whole days elapsed since birth
- 1
Elapsed milliseconds
980,726,400,000Milliseconds between the birth date and the reference date. - 2
Age in days
floor(980,726,400,000 ÷ 86,400,000) = 11,351
How does this calculator work?
Enter a birth date and an optional reference date (today by default) to see your exact age. The tool reports calendar years and months plus the precise count of weeks, days, hours and minutes elapsed, each floored to whole units, so you instantly know how many days old you are.
Formula
How this is calculated
Enter your birth date and, optionally, a reference date. The reference defaults to today, so leaving it as the prefilled value gives your current age. Both fields accept an ISO date (YYYY-MM-DD); the tool parses them into JavaScript Date objects and computes the elapsed milliseconds as reference minus birth.
Larger units are derived two ways. Years and months use a true calendar difference: total whole months equals (yearDiff × 12 + monthDiff), reduced by one if the reference day-of-month has not yet reached the birth day-of-month, and years is the floor of months ÷ 12. Weeks, days, hours and minutes are derived from the raw millisecond span: days = floor(ms / 86,400,000), weeks = floor(days / 7), hours = floor(ms / 3,600,000) and minutes = floor(ms / 60,000).
All results are floored to whole units, so partial periods are dropped rather than rounded up. The calculator assumes the reference date is on or after the birth date and returns nothing for invalid dates or a reference earlier than birth. Because day-level math is used, daylight-saving shifts and leap years are absorbed naturally into the day and hour totals.
Frequently asked questions
Years and months follow the calendar (months have varying lengths), while days, weeks, hours and minutes come from the exact elapsed time, so they stay consistent regardless of month length.
Use ISO format, YYYY-MM-DD (for example 1995-06-15). The reference field is prefilled with today, which you can change to any later date.
Each unit is floored to a whole value, so a partial week, day or hour is not counted until it fully completes.
Also known as
TG we-Calculate Editorial Team. (2026). Age in Years, Months, Weeks, Days, Hours [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/age-in-units
TG we-Calculate Editorial Team. "Age in Years, Months, Weeks, Days, Hours." TG we-Calculate. 2026. https://we-calculate.com/calculator/age-in-units.
TG we-Calculate Editorial Team, "Age in Years, Months, Weeks, Days, Hours," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/age-in-units
@misc{wecalculate_age_in_units, title = {Age in Years, Months, Weeks, Days, Hours}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/age-in-units}}, year = {2026}, note = {TG we-Calculate} }
Did this calculator help you?