Convert tools

Age Calculator

Calculate completed years of age on a chosen reference date, including birthdays and leap-day births.

Convert in your browser · No sign-up

For a February 29 birthday, February 28 is the anniversary in non-leap years. This is a calendar convention, not a legal age determination.

Up to 100,000 UTF-16 units per input and 1,000,000 per result. See the supported formats and examples below.

How to use

  1. Calculate completed years of age on a chosen reference date, including birthdays and leap-day births.
  2. Choose the mode or options, then run the tool.
  3. Review the result, then copy or download the TXT file.

Example

2000-06-15 → 2026-06-14 = 25 y

Details and limitations

For a February 29 birthday, February 28 is the anniversary in non-leap years. This is a calendar convention, not a legal age determination.

Text stays in your browser; it is not sent to a conversion server.

FAQ

Age Calculator — What are the supported inputs and limits?

For a February 29 birthday, February 28 is the anniversary in non-leap years. This is a calendar convention, not a legal age determination.

Format references

Tool page updated: