Age Calculator
Enter a date of birth on or before the "as of" date.
Age is calculated using calendar months and days (not a 30-day average) — e.g. Feb 28 to Mar 31 counts as 1 month, 3 days.
Free age calculator that shows your exact age in years, months, and days, plus days until your next birthday — using real calendar-based math, not a 30-day-average approximation.
How it works
- Enter your date of birth using the native date picker (no ambiguous MM/DD vs DD/MM typing)
- Optionally change "Calculate age as of" to any other date
- See your exact age, days until your next birthday, and total days/weeks/months lived
Frequently asked questions
How is the age calculated?
Using real calendar months and days — for example, Feb 28 to Mar 31 counts as 1 month and 3 days, based on the actual number of days in each month. This avoids the 30-day-average approximation some calculators use, which can be off by a few days.
Can I calculate my age on a future or past date?
Yes — change "Calculate age as of" to any date, past or future, to see your age (or age-to-be) on that date.
What happens if I was born on Feb 29 (leap day)?
In non-leap years, your birthday is treated as March 1 — the day right after Feb 28, matching how most leap-day birthdays are conventionally observed.
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From the blog
Update history
- 2026-09-01 Launched: age calculator with calendar-accurate years/months/days, days until next birthday, and total days/weeks/months lived — plus an "as of" date field for calculating age on any date. Entirely client-side.