Percentage Calculator
Find percentages, percentage of a number, and percentage change in seconds.
Age Calculator
Find an exact age in years, months and days.
How age is calculated
Subtract the birth year, month and day from the target date, borrowing days from the previous month and months from the previous year when needed — the same method used on official forms.
Worked example
Someone born on 15 June 2000 was exactly 26 years old on 15 June 2026, and 26 years, 1 month old on 15 July 2026.
How to use this calculator
- Enter the date of birth.
- Optionally choose a different end date.
- Select Calculate.
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Frequently asked questions
Can I calculate age at a future or past date?
Yes. Enter any date in the second field and the age on that date will be shown.
Does it count leap years?
Yes for total days, because it uses the real calendar difference between the two dates.