How to Calculate Age Between Dates

Basic idea

Age is the difference between a birth date and a target date. It is usually shown in years, months and days.

Why it is not just days divided by 365

Years and months have different lengths. Leap years also affect the result.

Example

If someone was born on May 10, 2000 and the target date is May 10, 2025, the age is exactly 25 years.

Practical use

Age calculators are useful for forms, documents, events, school records and date planning.

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