Age Calculator
Find the exact time between two dates: age in years, months and days, plus the totals in days, weeks and hours. Leave the second date as today to get someone's current age.
0 Total days | 0 Total weeks | 0 Total hours |
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- Enter the start date (for age, the birth date).
- Enter the end date — it defaults to today.
- See the exact difference in years, months and days.
- The totals below show the same span in days, weeks and hours.
How exact age is calculated
Age is not just "this year minus that year". The correct method counts full years first, then the remaining full months, then the leftover days — accounting for months of different lengths and leap years. That is why someone born on March 31 has a slightly different day-count than someone born on March 1, even in the same month. This calculator does the borrowing between months exactly, so the result matches how age is legally counted.
Days between dates
The totals are handy for project deadlines, pregnancy weeks, notice periods, subscription spans and trivia ("I have been alive 10,000 days"). Weeks are simply total days divided by seven; hours multiply days by 24. Because everything runs in your browser using its date engine, leap years and month lengths are always correct.
Frequently asked questions
Does it account for leap years?
Yes. The calculation uses real calendar dates, so February 29 and varying month lengths are handled automatically.
Can I calculate a future date difference?
Yes — set any end date, past or future. The result shows the span either way.
How is the "next birthday" found?
It takes the start date's month and day in the current or next year, whichever is still ahead, and counts the days remaining.
Is my data stored?
No. Dates are processed only in your browser and never sent anywhere.