Age calculator
Exact age or the difference between any two dates.
Exact difference
36 years, 7 months, 30 days
- Total months
- 439
- Total weeks
- 1913
- Total days
- 13391
Next anniversary in 123 days, on 2027-01-15.
Enter a date of birth and a date to measure to. You get the exact difference in years, months and days, plus the totals — and how long until the next anniversary.
How to use it
- Enter the date of birth, or any start date.
- Set the end date — today by default.
- Read the exact difference and the totals.
Why use this tool
Completely private
Everything runs inside your browser. Your files and text are never sent to a server.
Free, with no limits
No sign-up, no watermarks and no cap on how many times you can use it.
Instant results
There is no upload or queue to wait for, so results appear as fast as your device can work.
Works on any device
Runs in any modern browser on phone, tablet or desktop. Nothing to install.
Frequently asked questions
- How are months counted?
- By the calendar, not a flat 30 days. From 31 January, one month lands on 28 February, because February has no 31st. That matches how people talk about months and how date libraries behave.
- What about someone born on 29 February?
- In a common year they age on 28 February. That follows from the same clamping rule and matches how most jurisdictions treat leap-day birthdays, though a few use 1 March.
- Can I measure future dates?
- Yes. The order does not matter — the difference is always reported as a positive amount, so you can use it as a countdown as easily as an age.
- Why do total months and years plus months differ?
- They do not: total months is the same figure expressed differently. 3 years and 5 months is 41 total months. Days beyond that are shown separately rather than rounded into it.