Age Calculator Online: Exact Age from Date of Birth
Calculate your accurate age in years, months, weeks, days, and hours from your date of birth using our free online age calculator. Updated for 2026.
How to Calculate Age from Date of Birth Online
Calculating age from a date of birth (DOB) sounds simple — subtract one year from another — but the calendar gets in the way. Months have different lengths, leap years add a 29th of February every four years, and time zones can shift a birth date by a full day. A proper age calculator by DOB handles all three quietly so you never have to.
How Old Am I Today? — the exact formula
The standard rule is: subtract birth year from current year, then adjust down by one if the current month/day hasn't reached the birth month/day yet. Our calculator applies this rule and then computes the residual months and days by borrowing from the previous calendar month, so you always get a whole-number, government-form-ready answer.
Age between two custom dates
Set the target date to anything — past, present or future. This is useful for exam eligibility ("age as on 1 Jan 2026"), passport applications, retirement planning, or simply counting the days until your next milestone birthday. For structured differentials in weeks and intervening months, jump to our Chronological & Date Difference Calculator.
Beyond chronological age
Chronological age is only one lens. Your biological age, your pet's equivalent human age, or a mother's gestational week count all use different formulas — and DrHint gives each one a dedicated, purpose-built tool below.
Frequently Asked Questions
How does an age calculator by DOB work?+
It takes your date of birth and the target date (today by default), then subtracts calendar years, months and days while accounting for leap years so the total is exact — not an estimate.
How old am I today, precisely?+
Enter your date of birth above and keep 'Today' as the target date. You'll instantly see your age in years-months-days plus total weeks, days, hours and minutes lived.
Is this calculator accurate for legal or job applications?+
Yes. The logic uses the standard chronological method used by government forms, exam boards and HR systems — years first, then remaining months, then remaining days.
Can I calculate age between two custom dates?+
Yes — change the target date to any past or future date. For deeper date-difference outputs (total weeks, intervening months), use our Chronological & Date Difference Calculator.
Does it work for future birthdays?+
If your target date is before the date of birth, the tool tells you how many days until that birthday instead of returning a negative age.
Specialized Advanced Calculators Available on DrHint
Purpose-built age tools — each one runs 100% locally in your browser for instant answers.