Tiny Toolkit

Age Calculator — Exact Age in Years, Months & Days

Enter a date of birth to see the exact age in years, months, and days — along with total days lived, weeks, months, and days until the next birthday. You can optionally set a custom reference date to calculate how old someone was or will be on a specific occasion. All calculations account for varying month lengths and leap years.

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Frequently Asked Questions

How is exact age calculated?
The calculator counts complete years, months, and days between the date of birth and the reference date, accounting for varying month lengths and leap years.
Can I calculate age as of a specific date?
Yes. Click 'Custom date' to set the reference date to any past or future date. This is useful for calculating how old someone was or will be on a specific occasion.
How are the 'days to birthday' calculated?
The calculator finds the next occurrence of your birthday month and day (in the current or next year) and counts the days from today to that date.

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