Age Calculator

Work out exact age in years, months and days from any birth date.

What Does the Age Calculator Do?

The Age Calculator works out an exact age from a date of birth: years, months and days, calculated calendar-accurately (leap years and varying month lengths included). It also shows lifetime totals — months, weeks, days and hours lived — and counts down to the next birthday. By changing the "calculate age on" date you can find an age at any point in time, past or future.

How to Calculate an Age

  1. Pick the date of birth.
  2. Leave "calculate age on" as today, or set any other date.
  3. Click Calculate Age — the breakdown, totals and birthday countdown appear instantly.

More Than Birthdays

  • Official forms — visa, insurance and school applications often ask for age in exact years and months.
  • Eligibility checks — verify someone reaches a required age by a cutoff date (set "calculate on" to the deadline).
  • HR and admin — service duration, retirement dates, membership anniversaries — the same math applies to any start date.
  • Milestones — discover when you turn 10,000 days old (a surprisingly popular celebration).
  • Historical research — how old was a person on a specific historical date?

The calculation runs in your browser and no dates are transmitted or stored.

Frequently Asked Questions

How does the calculator handle leap years?

Fully — the year/month/day breakdown walks the real calendar, so February 29 birthdays and leap-year day counts come out exactly right. The total-days figure is the true count of days elapsed.

Why does "months" differ from what I expected?

Because months have different lengths, age in months depends on the actual calendar path. The calculator borrows days from the correct preceding month, matching how authorities compute official ages.

Can I calculate age at a past or future date?

Yes — set the "calculate age on" field to any date. Useful for eligibility cutoffs ("will she be 18 by election day?") and historical questions alike.

When is my Feb 29 birthday in a common year?

The countdown targets February 28 in non-leap years by treating the anniversary as the same month/day clamped to the calendar — the convention most jurisdictions use is either Feb 28 or Mar 1; check local rules for legal purposes.