Age Calculator
Work out an exact age in years, months and days from a date of birth.
Runs entirely in your browser. Nothing you type is uploaded.
About this tool
Enter a date of birth and, optionally, the date to measure against. You get the age in full years, months and days, the total number of days lived, and how long until the next birthday. All arithmetic is plain calendar arithmetic with no time zone involved.
Questions & answers
- How is age counted?
- The year only increases once the birthday has passed. Someone born on 1 March 2000 turns 25 on 1 March 2025, not on 1 January 2025.
- What happens with a 29 February birthday?
- In non-leap years the birthday is treated as 1 March for counting purposes, which is the common civil convention.
- Does this tool send my data to a server?
- Runs entirely in your browser. Nothing you type is uploaded.
Related tools
Need the full version? DateLab goes much deeper on this topic.