Utility Tools
Date Difference Calculator
Find the exact number of days, weeks, months and years between two dates — with an option to include the end date in the count (useful for hotel nights, project days or age-at-end calculations). The breakdown uses true calendar arithmetic rather than a fixed 30-day month.
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How to use
- 1
Pick the start date
Use the first date picker. Defaults to empty so you can choose any start point.
- 2
Pick the end date
Use the second date picker. Defaults to today. Use the Swap button to flip the two.
- 3
Toggle end-date inclusion
Enable “Include end date in the count” if you need hotel-night style counting (Mon → Tue = 2 days).
- 4
Read the breakdown
The big number shows years, months and days. The list below shows totals in days, weeks, months, years, hours and minutes.
Common use cases
- Count days remaining until a deadline, vacation or product launch.
- Calculate project duration in working days for a statement of work.
- Work out the age of an account, contract or warranty from its start and end dates.
- Verify hotel-night counts or rental-day charges by including the end date.
Limitations
- Years / months / days use calendar arithmetic. A 31 Jan → 28 Feb span is 28 days / 1 month, not 30 days — this matches how a person reads a calendar.
- Hours and minutes are derived by multiplying the day count by 24 and 60 respectively; daylight saving transitions are not modelled.
- The end-date toggle adds one day only when the end date is on or after the start date. Reversed ranges show the absolute span without adjustment.