Age Calculator
Find an exact age in years, months and days, or measure the time between any two dates. All calculation happens on your device.
How to calculate age
- Enter the birth date (or any starting date) in the first field.
- Enter an "as of" date, or tap Today to use the current date.
- The exact age in years, months and days appears instantly.
- Check the total days and weeks below the main result.
FAQs
How is age calculated exactly?
The tool uses the civil calendar, adding whole years then months then days, so it correctly handles leap years and months of different lengths.
Can I use it for dates other than birthdays?
Yes. Use any two dates to measure the duration between them, such as time since a start date or until a deadline.
What do total days and total weeks mean?
They are the raw number of days and whole weeks between the two dates, useful for tracking a pregnancy, a subscription or a project.
What happens if the dates are in the wrong order?
The calculator shows an error and asks you to make the second date equal to or later than the first date.
Related Tools
Why use an age calculator?
Working out an exact age by hand is fiddly because months and leap years vary in length. A calculator gives a precise answer instantly.
- Find a precise age for a form, application or profile.
- Measure the exact time between two milestones.
- See total days and weeks for planning and tracking.
Tips and Limits
The "as of" date defaults to today. The result uses the civil calendar for exact years, months and days, and everything is computed locally in your browser.