Common uses
- Exact age: full years, months, and days since a date of birth.
- Length of service: years of experience or contract duration.
- Countdowns: how many days until an event or deadline.
- Legal and contract periods: leases, warranties, or grace periods.
How it is calculated
The difference is given in full years, months, and days, using each month's actual number of days rather than an average, and also as total days and weeks for anyone who needs a single figure.
Frequently Asked Questions
Are the first and last days both counted?
No. The calculator gives the number of days elapsed between the dates. To include both days in the count, add one day to the result.
Can I use future dates?
Yes. Enter a future date as either date to see how long remains until it.