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Age Calculator

Age Calculator

Find your exact age in years, months, days, weeks, hours and minutes. Enter your date of birth and any target date — leap years and month lengths are handled correctly.

= Years
26
= Months
6
= Days
26
= Total days
9,704
= Total weeks
1,386
= Total hours
232,896
= Total minutes
13,973,760

The Age Calculator works out your exact age from your date of birth to any target date. Instead of returning a rough number of years, it breaks the difference down into years, months and days and also gives you total weeks, hours and minutes lived — a handy figure for birthdays, retirement planning, insurance forms and school admission cut-offs.

How the age calculator works

We compare the two dates using calendar arithmetic. First we subtract the birth year from the target year. Then we adjust the year down if the target month/day hasn't yet reached the birth month/day. Finally we compute the leftover months and days by borrowing from the previous month's real length — so February with 28 or 29 days is respected, and 31-day months are not shortened to 30.

The formula behind it

  1. Years = target year − birth year (minus 1 if the birthday hasn't happened yet this year).
  2. Months = target month − birth month (borrow 12 months from the year if negative).
  3. Days = target day − birth day (borrow the days in the previous calendar month if negative).
  4. Total days = floor((target − birth) / 86,400,000 ms).

Step-by-step example

Suppose you were born on 15 March 1990 and today is 27 July 2026. The target month (July) is after March, so no year is borrowed and you are 36 years old. From 15 March to 15 July is 4 months; from 15 July to 27 July is another 12 days. Final answer: 36 years, 4 months, 12 days.

Common use cases

  • Schools and universities checking admission eligibility on a specific cut-off date.
  • Government forms, passports and driving-licence applications requiring exact age.
  • Insurance and pension quotes where premiums step at whole-year boundaries.
  • Sports leagues that classify players into under-14, under-16, under-18 brackets.
  • Retirement planning: how many days are left until your 60th or 65th birthday.

Tips for accurate results

  • Use the ISO format (YYYY-MM-DD) so there's no month/day ambiguity.
  • For legal documents, set the target date to the deadline, not today.
  • If you're near midnight in a different time zone, adjust the birth date by one day.

Common mistakes

  • Treating months as a flat 30 days — real months vary from 28 to 31.
  • Forgetting that leap years add a 29 February every 4 years (with the 100/400 rule).
  • Counting the birthday itself as +1 day — the calculator counts completed days only.

Frequently asked questions

How is my exact age calculated?+
We take your date of birth and compare it to today (or a target date), then break the difference into years, months and days using calendar arithmetic — so leap years and different month lengths are handled correctly.
Does the age calculator account for time zones?+
It uses your browser's local date. If you were born in a different time zone, results can shift by one day near midnight; adjust the target date one day forward or back to compare.
Why does my age in months differ from years × 12?+
Months have different lengths (28–31 days). We count whole calendar months between the two dates, not a flat 30-day approximation.
Can I calculate age on a future or past date?+
Yes. Set the target date to any date in the past or future to find how old someone was — or will be — on that day.
Is the calculator accurate for very young ages?+
Yes. Under one year old, the result shows 0 years plus the exact number of months and days.