🎂 Age Calculator
Exact age in years, months and days — plus total days lived and a countdown to the next birthday.
36 years 6 months 17 days
Calculated on your device — your birthdate is never transmitted.
How the age calculator works
The calculation walks the calendar rather than dividing day counts: full years from birthday to birthday, then full months, then leftover days — the same way age is legally reckoned. That handles unequal month lengths and leap years correctly: someone born 29 February completes a year of age on 1 March in non-leap years in most jurisdictions.
Dividing days-lived by 365.25 gives a decimal "age" that drifts a day or two around birthdays — fine for estimates, wrong for forms and eligibility rules, which use the calendar walk this tool performs.
Frequently asked questions
How is exact age calculated?
Calendar-style: count complete years first (has this year's birthday passed?), then complete months, then remaining days. This matches how ages are used legally and administratively.
What about leap-year birthdays (29 February)?
In common years the birthday is generally observed on 1 March for legal purposes (e.g. UK law), though some jurisdictions use 28 February. This calculator counts the year as complete once the calendar reaches 1 March.
Why does "total days" not equal years × 365?
Leap years: roughly one year in four has 366 days. Thirty years of life spans about 10,957 days, not 10,950.
Can I calculate age at a date other than today?
Yes — set the "age at" date to anything: a form deadline, a school cutoff, a historical date.
Is my date of birth sent anywhere?
No — the calculation runs entirely in your browser. A birthdate is personal data; that is exactly why this tool is client-side.