Date Difference Calculator
Calculate the exact number of days, weeks, and months between any two calendar dates.
- Days
- 365
- Weeks
- 52.14
- Months
- 11.99
How it works
Days is an exact count: the millisecond gap between the two dates divided by milliseconds per day. Weeks is days ÷ 7. Months is days ÷ 30.436875 — the average length of a month (365.2425 ÷ 12, using the average Gregorian calendar year), since calendar months don't have a fixed length.
FAQ
Why is the 'months' figure not a whole number?
Because months vary from 28 to 31 days, there's no single exact day-to-month conversion that works for every date range. This calculator uses the average month length, which is standard practice for this kind of estimate but won't always match counting calendar months by hand.