§ 01 / TOOL
Age Calculator.
STATUS ACTIVECALENDAR GREGORIANTZ UTC
> INPUT
BIRTH DATE
AS OF (DEFAULT: TODAY)
AGE 25 YEARS
LIVE
// EXACT
25 Y10 M7 D
BORN June 15, 2000 · AS OF April 22, 2026
Days
9,442
Weeks
1,348
Hours
226,608
Minutes
13,596,480
// NEXT BIRTHDAY
54
DAYS · June 15, 2026
§ 02 / ABOUT
Counting the time between two dates.
This calculator does more than subtract two dates. It breaks the interval into exact years, months, and days, and also shows total weeks, days, hours, and minutes — all based on the Gregorian calendar with leap years handled correctly.
// WHAT THE NUMBERS MEAN
- Years / months / days — the normal way to report age. A person born 2000-06-15 is "25 years, 10 months, 6 days" old on 2026-04-21.
- Total days / weeks / hours / minutes — useful for milestones, visas, warranties, or just for the fun of counting your life in heartbeats.
- Next birthday — the number of days until the next anniversary of the birth date.
// LEAP YEARS AND FEB 29
Feb 29 birthdays are rare (one in 1,461). In non-leap years, most implementations treat the "birthday" as Feb 28 or Mar 1 depending on jurisdiction — this tool uses Mar 1, the most common legal convention in the US. Time zones are treated as UTC for consistency.
Related: Countdown, TDEE, BMI / Body Composition.
§ 02 / FAQ
Questions. Answered.
How is age calculated?+
We compute the difference between your birth date and the "as of" date. Years are completed birthdays, months are completed months past your last birthday, days are leftover. Total days/weeks/hours/minutes are absolute counts from the moment of midnight on each date in UTC.
Can I find out how old I'll be on a future date?+
Yes — set the 'as of' field to any date and the calculator answers as if today were that date. Useful for milestones, retirement planning, or just curiosity.
What about leap years and unusual birthdays (Feb 29)?+
We do calendar-correct math: a Feb 29 birthday only "hits" on leap years, but the year-month-day breakdown still shows the right age. The countdown to the next birthday rolls to Feb 28 in non-leap years for display purposes.
Why are everything in UTC?+
Birthdays are dates, not moments — so we treat each date as midnight UTC to avoid timezone weirdness. The total-hours/minutes counts are exact UTC differences. The values change once per day at midnight UTC, not at midnight in your local time.
Can I share or bookmark a calculation?+
Yes. The URL updates as you type — /age/1990-05-15 means "born May 15, 1990, as of today". /age/1990-05-15-to-2030-01-01 means "as of January 1, 2030". Share or bookmark either form.
Is my data saved or sent anywhere?+
No. The calculation runs in your browser. The only persistence is the URL, which only your browser knows about until you share it.
§ 04 / TOOLS
Related calculators.
§ 05 / READING