Work out your exact age in years, months and days — plus total days lived and your next birthday.
🔒 This tool runs entirely in your browser. Nothing you enter or upload is sent to our servers.
How to use the Age Calculator
- Enter your date of birth.
- Optionally change the “age at” date (it defaults to today) to find your age on a past or future date.
- Read your exact age, total time lived and days until your next birthday.
About this tool
This calculator counts calendar years and months first, then the remaining days, which is how ages are conventionally stated (“32 years, 4 months and 12 days”). It correctly handles leap years and months of different lengths.
It also converts your age into total months, weeks, days and hours — handy for forms that ask for age in months (common for babies) or just for curiosity.
Frequently asked questions
How is age calculated?
Full years are counted from birthday to birthday, then full months, then the leftover days. If your birthday hasn’t happened yet this year, the year is not counted.
What if I was born on 29 February?
In non-leap years your birthday is treated as 1 March for the purpose of counting a full year, which is the most common legal convention.
Can I calculate the age of something other than a person?
Yes — use it for a company, a pet, a marriage anniversary, or the time since any date.
Is my date of birth stored?
No. Everything is calculated inside your browser and nothing is sent to a server.