📅 Date Difference Calculator
Calculate the difference between two dates. See days, weeks, months, years, hours, and a human-readable summary — all in your browser.
Pick two dates to see the difference between them.
About the Date Difference Calculator
This calculator measures the time between two dates. It returns the difference in days, weeks, months, years, hours, and minutes, plus a natural-language summary such as "2 years, 3 months, 15 days". The end-date option lets you count inclusively, which is useful for project durations and contract terms.
How the calculation works
- Total units (days, hours, minutes) — Computed from the raw millisecond difference between the two dates.
- Calendar breakdown (years, months, days) — A calendar-aware difference that borrows from the previous month or year as needed, matching how people normally describe elapsed time.
- Inclusive mode — When enabled, one extra day is added to the day count, treating both start and end dates as full days.
How to use
- Pick the First date and Second date using the date pickers.
- Tick Include end date in the count if you want an inclusive duration.
- Click Calculate to see all the breakdowns at once.
Frequently asked questions
Does the order of the two dates matter? No. The calculator always reports a positive duration. Swap the dates and the result is the same.
Why does the human-readable summary sometimes differ from the day count? The summary uses calendar months (which vary in length), while the day count is exact. Both are correct — they just measure time differently.
Are leap years handled? Yes. Calculations use real calendar dates, so leap years and varying month lengths are accounted for.
Is my data stored? No. Everything runs locally in your browser.