Age Calculator
Calculate exact calendar age on today’s date or any other comparison date.
Calculations happen locally in your browser.
How to use this calculator
- Enter a date of birth and the date on which age should be measured.
- Review the live result and use Copy result when you need to share it.
How the calculation works
Completed years are counted first, followed by completed calendar months and remaining days. Month-end and leap-day anniversaries are clamped to valid calendar dates.
Formula
Age = completed calendar years + months + remaining days
Step-by-step calculation
- Enter a date of birth and the date on which age should be measured.
- Completed years are counted first, followed by completed calendar months and remaining days. Month-end and leap-day anniversaries are clamped to valid calendar dates.
- Check the displayed result, then copy it if needed.
Worked example
Someone born 15 January 2000 is 26 years, 2 months, and 5 days old on 20 March 2026.
Risk guidance
Frequently asked questions
How are leap-day birthdays handled?
Calendar anniversaries are clamped to a valid day in the comparison month and year.
Does this tool send my inputs anywhere?
No. The interactive calculation runs in your browser and this site does not submit tool inputs to a backend.
How should I use the result?
Check that the entered units and values match your situation, especially around dates, breaks, and rounding.
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