How to use the Age Calculator
- Enter the date of birth.
- Optionally change “Age on” to calculate the age on a past or future date (for example a deadline or an event).
- Read the exact age in years, months and days, plus totals in months, weeks, days, hours and minutes.
- See the weekday of birth, the next birthday and how many days until it.
How age is calculated
Age in completed years counts how many birthdays have passed. The remaining months and days are counted from the last “monthly birthday”, borrowing the correct number of days from the previous month — so the result matches how people (and most official forms) state age. Totals like days and weeks are exact calendar day differences, including leap years.
Good to know
- Leap-day birthdays (29 February): in non-leap years the birthday is usually celebrated on 28 February or 1 March; legally it depends on the country.
- Age on a specific date is useful for eligibility checks — school entry, insurance, competitions or retirement dates.
- The Chinese zodiac animal is based on the calendar year; strictly it changes at Chinese New Year (late January to mid-February).
For the time between any two dates use the Date Difference Calculator, for meeting times across countries the Time Zone Converter, and for timestamps in code the Unix Timestamp Converter.
Tools that pair well with the Age Calculator
- Percentage Calculator — Seven everyday percentage calculations on one page.
- Possibility & Combination Calculator — How many possibilities are there?
- Random Number Generator — Generate random numbers (with or without duplicates), pick winners from a list, shuffle names, split groups into teams, flip coins and roll dice — using your browser’s cryptographically secure randomness.
- Unit Converter — Convert between metric, imperial and technical units in ten categories — with a two-way converter and a table of every unit at once.
Frequently asked questions
How do I calculate my exact age?
Enter your date of birth — the calculator returns your age in completed years, months and days, plus totals such as the number of days you’ve been alive.
Can I calculate age on a future date?
Yes. Change the “Age on” date to any date in the past or future, for example to check how old someone will be on a specific day.
How are leap years handled?
Day totals are exact calendar differences, so every 29 February is counted. Years and months follow calendar months rather than fixed 30-day blocks.
Is my birth date saved?
No. It stays in your browser; it’s only added to the page URL so you can bookmark or share the result if you want.