Enter a date of birth to get an exact age in years, months and days as of today — or set the second date to measure the gap between any two dates. It also shows the total in days and weeks, and how long until the next anniversary.
How age is actually calculated
Age isn't just days divided by 365. A correct calculation counts whole calendar years first, then the leftover months, then the leftover days — accounting for the fact that months have different lengths and that leap years add a 29 February. That's why someone can be "34 years, 2 months and 6 days" rather than a raw day count. This tool does that calendar-aware breakdown, and also gives you the raw totals (total days, total weeks) for when you need a single number.
When and why you'd use it
- Exact age — for forms, eligibility, or simple curiosity ("how old am I today?").
- Anniversaries and milestones — how long you've worked somewhere, or how old a project or relationship is.
- Countdowns — days until a birthday, event, or deadline.
- Durations — the precise gap between two historical dates.
Worked examples
Frequently asked questions
How are leap years handled?
Because the calculation counts real calendar dates rather than assuming 365-day years, leap days are handled automatically — the day and month have to actually arrive for the count to tick over.
Why not just divide the total days by 365?
That drifts off by several days over a lifetime, because roughly one year in four has 366 days. Counting calendar years, then months, then days is exact.
Does it include today in the count?
The difference is measured up to the end date you choose (or today). A person born today is 0 days old; your age ticks up on each birthday.
Is my date of birth stored anywhere?
No. The calculation runs entirely in your browser using your device's clock. Nothing is uploaded or saved.