How it works
Subtract the birth year from the reference year, then subtract one if the birthday is still ahead in the reference year. The reference date is editable; the initial date is a worked example.
Inputs and units
| Input | Example value | What to enter |
|---|---|---|
| Date of birth | May 15, 1995 | Choose a valid calendar date. |
| Age on this date | October 8, 2026 | Choose a valid calendar date. |
Worked example
Show example inputs and results
This example is generated by the same calculation engine using the starting values in the form. Your own inputs produce your own result.
- Date of birth
- May 15, 1995
- Age on this date
- October 8, 2026
Complete example results
- Completed years
- 31
- Total days
- 11,469
Reading the result
Elapsed calendar time differs from completed years or months. Check interval endpoints, leap-year conventions and any working-day scope.
Questions and answers
Can I use the example values for my own calculation?
The example values illustrate the calculation. Replace every input with your own information, especially dates, rates and the selected operation.
How are February 29 birthdays handled?
In a non-leap year, this calculator increases the completed age on March 1. This is a stated calculation convention, not a determination of legal age rules.
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
Are my inputs sent to a server?
The calculator processes inputs in your browser. Its code does not send your values to a server.