Age Calculator

Calculate your exact age from date of birth

Type a date or click to pick

What is Age Calculator?

An age calculator determines the precise time elapsed between two dates — most commonly a date of birth and today — broken down into years, months, weeks, days, hours, and even minutes. While a simple subtraction of years gives a rough age, an accurate age calculation must account for varying month lengths, leap years (which add an extra day every 4 years, with exceptions for century years), and the specific day of the month.

Age calculations matter in many real-world situations: applying for jobs, government documents (where exact age on a specific date is required), pension and retirement calculations, medical contexts (paediatric drug dosing is often based on exact age in months), insurance applications, school enrolment (many systems have specific cut-off dates), and legal age verification.

Altairys's Age Calculator computes your exact age instantly based on any birth date and a target date (defaulting to today). It shows your age in multiple formats simultaneously — years, months, days, total weeks, total days, and time until your next birthday — so you always have the precise figure you need. No sign-up, no ads, and instant results directly in your browser.

How to Use Age Calculator

  1. Enter your birth date

    Type or pick your date of birth using the date input.

  2. Set the target date

    Default is today, but you can calculate age on any past or future date.

  3. View your exact age

    See your age in years, months, days, weeks, total days, and hours instantly.

  4. Check your next birthday

    See how many days remain until your next birthday celebration.

Key Benefits

Exact to the day

Accounts for leap years, varying month lengths, and the exact calendar date.

Multiple formats

View age in years, months, days, total weeks, total days, and hours at once.

Instant results

Results update in real time as you change the date — no button to press.

Any date supported

Calculate age for any historical or future date, not just today.

Frequently Asked Questions

The calculator correctly accounts for February 29 birthdays and the extra days in leap years, ensuring the result is always accurate to the day.

Yes — change the "as of" target date to any date in the past or future to calculate age at that point in time.

Because months vary in length (28–31 days) and the calculation tracks partial months. An age of 1 year and 3 months is 15 months, not 15.X×28 days.

Yes. Leap year birthdays (February 29) are handled correctly — on non-leap years the birthday is counted on March 1.

Yes, this tool provides the exact age calculation used for legal purposes — important for things like retirement age, driving eligibility, and school enrolment cut-offs.

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