Age Calculator
Calculate the exact age between two dates, to precisely determine age differences or the span between two life events. Runs in your browser, GDPR-compliant.
Your inputs are processed in your browser and are not transmitted to our servers. Note: third-party resources (e.g. advertising and analytics from Google/Cloudflare) and an optional PayPal donation link may transfer data when loading or when clicked. Browser extensions or plugins may be able to read content that is visible in the input fields.
The result will appear here …
How to use this tool (video)
This video is hosted on YouTube. When you play it, data may be sent to Google.
Age Calculator
The age calculator determines the exact age between two dates. Whether you want to know how old you are or how many years separate two life events, this tool gives you the precise answer in years, months, and days.
How it works
The calculation works by subtracting the birth date from the current date or any reference date. First the year difference is determined, then it checks whether the birthday has already occurred in the current year. If the birthday has not yet arrived, one year is subtracted. Then the remaining months and days are calculated individually. For example, someone born on March 14, 1990, checked on September 10, 2025, has 35 full years because the birthday in 2025 has already passed. Then 5 full months from March 14 to August 14 plus 27 additional days to September 10, giving 35 years, 5 months, and 27 days.
What the tool can and cannot do
The age calculator provides the difference between two dates in years, months, and days. It cannot generate future age projections and does not account for leap years at the day level in anniversary calculations, working instead with calendar days. The tool does not display birth dates in alternative formats and does not calculate pension amounts or insurance contributions. It is a pure date-difference utility without financial or medical functions.
Why local processing in the browser
All calculations happen directly in your browser. Your birth dates and reference dates are never sent to a server. There is no upload, no server log files, and no access by third parties. You need no account and no registration. After the page loads, the age calculator works offline too because all resources are cached locally. There is no server that could be attacked and your personal data is not transmitted over the network. You can try different dates as often as you like and discard results because nothing is stored or tracked.
Frequently asked questions
How accurate is the age calculator?
The age calculator is as accurate as the calendar date you enter. It computes the exact difference in years, months, and days, accounting for the actual number of days per month and leap years. The result is always mathematically correct.
Do I need to be online?
No, after the page has loaded once, the age calculator works offline. The required resources are cached in the browser and a flaky connection will not interrupt you.
Are my data uploaded?
No, your birth dates and reference dates are never sent to a server. Everything is processed locally in your browser with no upload and no third party access.
Can I calculate age in months or days?
Yes, the age calculator always shows the result in years, months, and days. The tool computes all three units simultaneously and gives you a complete picture of the timespan.
Does the calculator work with future dates?
Yes, you can enter future dates and the age calculator will show how old you will be at that point. The calculation works in both directions.
Is the tool free to use?
Yes, the age calculator is a free tool that runs directly in your browser. There are no hidden costs or limitations.