When to use age calculator
An age depends on the reference date, not just the difference between two years. Enter both dates to calculate completed calendar years and months, followed by the remaining days. Date-only arithmetic avoids daylight-saving changes altering the calendar count. You can use a historical reference date as well as today.
How it works
- Select a birth date.
- Keep today or select another reference date.
- Calculate the completed calendar age.
Try this example
Calendar years, months and days
Before you export or rely on the result
Future birth dates are rejected. For end-of-month dates, anniversaries are clamped to the last valid day of the month; legal age rules may use a different convention.
Does this tool upload my input?
No. This tool processes input in your browser. Optional advertisements are separate third-party content and load only when you allow ads. See the privacy notice for hosting logs and advertising details.
Can I use the result without creating an account?
Yes. Age Calculator is free to use without an account. Review the result against the limits above and the requirements of the app or document where you plan to use it.