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Age Calculator

Find your exact age in years, months, and days. See total days lived, days until your next birthday, and your age in months, weeks, and hours.

Enter Your Date of Birth
Date of Birth
Calculate age as of
Your Result

Fill in the details and
your result appears here.

Your Age
In Months
In Weeks
Total Days Lived
Next Birthday In
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Did You Know?
Legal age calculations
Most countries calculate legal age by counting completed years. Turning 18 means you have completed 18 full years since your date of birth — not just reached the date.

How to use this calculator

1

Enter date of birth

Pick from the date picker or type in YYYY-MM-DD format.

2

Choose reference date

Today calculates current age. Custom lets you calculate age on any past or future date.

3

Read results

See age in years, months, days — plus weeks, total days, and days until next birthday.

The formula explained

Age is calculated by subtracting the birth date from today (or the chosen date), accounting for leap years and month-end edge cases.

Age = (Today − DOB) in years, months, days

The calculation correctly handles months with different lengths and leap year birthdays.

Frequently Asked Questions

How do I calculate my exact age?

Subtract your birth date from today. This calculator handles months of different lengths and gives years, months, and remaining days precisely.

What happens if I was born on Feb 29?

On non-leap years, the birthday is treated as March 1 for calculation purposes. Most legal systems also use Feb 28 or Mar 1 in non-leap years.

Can I calculate age on a past date?

Yes — use Custom Date mode and pick any date. Useful for calculating age at a historical event or milestone.

How many days is 25 years?

Approximately 9,125 days, or 9,131 days if the period includes 6 or 7 leap years. This calculator counts exactly.

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