Age & Date Difference Calculator

Filling out an EPF claim or a visa application? Use this calculator to find the precise number of years, months, and days between any two dates without dealing with complicated leap year math.

Select Dates

Select a start and end date to calculate the exact duration in years, months, and days.

Why months are counted before days

Months have different lengths, so an age of years, months, and days only means something when the months are counted first and the leftover days measured against the actual calendar. Working purely in total days and dividing by 30.44 gives a different, and less useful, answer.

A month is added by landing on the same day number, or on the month end where that day does not exist. One month after 31 January is 28 February, so 31 January to 1 March is one month and one day. The same span in a leap year is one month and zero days, because February reaches the 29th.

Total days is not the same question as years and months
FromToYears, months, daysTotal days
1 Jan 20001 Jan 202626y 0m 0d9,497
31 Jan 20261 Mar 20260y 1m 1d29
29 Feb 202428 Feb 20262y 0m 0d730

Time zones, and why this tool builds dates from parts

A date typed into a date field has no time and no time zone attached to it. Parsing that text with the browser's default rules treats it as UTC midnight, which is the previous calendar day for anyone west of Greenwich -- so the same birth date can yield an age a day larger in Toronto than in Colombo.

This calculator constructs both dates from their year, month, and day components in local time instead, so a birth date means the same day whether you open the page from Colombo, London, or Melbourne.

Anniversaries that fall on 29 February

A date of birth on 29 February has a real anniversary only every fourth year. The convention followed here is to observe it on 1 March in common years, which is what the next-milestone countdown uses.

This is a convention rather than a universal rule. Some legal systems treat the anniversary as 28 February for age-threshold purposes, so check the specific rule where a date of majority or a deadline is at stake.

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Frequently asked questions

Because months have varying lengths (28, 30, or 31 days) and leap years exist, calculating the exact number of years, months, and days in your head is notoriously error-prone. This calculator uses standard calendar borrowing logic for 100% precision.

Count the whole years from your birth date to today, then the whole months since that anniversary, then the leftover days. Doing it by subtracting years alone is what produces an age that is wrong for anyone whose birthday has not yet come round this year.

Enter both dates and the calculator returns the difference in years, months and days as well as a total day count. It counts calendar days, so the answer is the same regardless of where in the world you are reading it.

Because months are not all the same length, so a difference has to be resolved month by month. Counting the months first and then the leftover days - borrowing from the preceding month where needed - is how people do it by hand, and it gives the answer that matches everyday intuition.

There is no 29 February in a common year, so the anniversary has to fall on either 28 February or 1 March by convention, and different institutions choose differently. Where a legal date matters - eligibility, a deadline - check which convention the body in question applies.

Enter your birth date as the first date and the future date as the second. The same calculation runs forwards, so you can check what age you will be on a specific day - useful for eligibility cut-offs, retirement dates, and school entry.

No. The calculator builds both dates from their calendar parts rather than from a timestamp, so a difference between two calendar dates is identical for a reader in Colombo and one abroad. This avoids the off-by-one error that timestamp-based date maths produces across time zones.

Enter today as the first date and the target as the second; the total-days figure is the countdown. It counts calendar days rather than working days, so subtract weekends and holidays yourself if you are planning around a working deadline.