Age Calculator
Exact age between two dates in years, months, and days, plus totals in months, weeks, and days, and a countdown table to the next five birthdays.
Fill in the values and calculate
The form sends itself back to this page — results print below, computed on the server.
No results yet: fill the form above and press Calculate.
About Age Calculator
Exact age from a birthday to a chosen date — today by default — in years, months, and days, with the same span also shown in total months, weeks, and days. Month and day counts borrow against the real calendar month, never an average month.
The table below lists the next five birthdays after the target date and counts the days and weeks until each, so the same page answers how long until the next birthday as well.
Questions about Age Calculator
Why do the leftover months and days not line up with 30-day months?
Because the count borrows against the actual month lengths: the extra days after the last birthday are measured in the real calendar month you are standing in, which is what people mean by an age.
Is the total-days figure exact?
Yes. It is a straight date difference, leap years included; the weeks figure is that count divided by seven, rounded down.
How are February 29 birthdays handled?
In non-leap years the birthday counts as February 28, which matches how most calendar tools treat it.
Can I check the age on a past date?
Any date works, past or future: put the date you want in the age-on field. Ages are only counted forward, so the birthday must come first.
Bookmark and homescreen
- Press Ctrl+B now (or Cmd+B on macOS) to bookmark this page in your browser.
- Drag this link to your bookmarks bar and it will always open this tool: Age Calculator.
- On a phone: open in Chrome/Safari and use "Add to Home Screen" — the site ships a homescreen icon and manifest, so it installs like an app.
- Two addresses work:
https://useful-utilities.com/age-calculator/andage-calculator.useful-utilities.com. Copy whichever you prefer.