Enter a date of birth to get an exact age in years, months and days — plus the totals, the day of the week you were born, and how long until the next birthday.
Result
Fill in the fields to see your result.
Age is counted the way a calendar counts, not the way a stopwatch does. The calculator subtracts the years, then corrects for the month and day: if this year’s birthday has not happened yet, one year is removed and the remainder is expressed in months and days borrowed from the previous month.
That last detail is why two calculators can disagree. Months do not have a fixed length, so "one month and five days" depends on which month you borrowed from. This calculator borrows from the month preceding the reference date, which is the convention used in civil registration and in most legal contexts.
The totals in days, hours and minutes are computed separately, straight from the elapsed time, so daylight saving changes cannot introduce an off-by-one. Everything is counted in whole calendar days in your own time zone.
years = year(now) − year(birth), minus 1 if the birthday has not occurred yet this year
The remaining months and days are then taken from the most recent birthday.
The year difference is 36, and the birthday has already passed in 2026, so the age is 36 years.
From 15 June to 28 August is 2 months and 13 days, giving 36 years, 2 months and 13 days — a little over 13 200 days in total.
Someone born on 3 December 1998, measured on 28 August 2026, is not 28 — the December birthday is still ahead.
The age is 27 years, 8 months and 25 days, and the next birthday falls 97 days later.
Because months vary in length and there is no single correct way to borrow from them. Going from 31 January to 1 March is either one month and one day or one month and two days depending on the direction you count.
This calculator borrows from the month before the reference date, which matches how civil registries and most legal systems count.
Someone born on 29 February has a real anniversary only in leap years. In common years the calculator shows 1 March, which is the convention in most jurisdictions. Some countries use 28 February instead, so check your local rule if it matters legally.
Yes. Change the reference date to anything you like — an age at a specific event, at a future deadline, or on a date in the past. The calculation runs the same way.
The decimal figure divides the total days by 365.2425, the average length of a year in the Gregorian calendar. It is a continuous measure and drifts slightly from the calendar count, which advances in whole years on your birthday.
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