Date Difference Calculator
Days between dates, business days included.
What people count days for
Project deadlines ("how many working days until launch"), notice periods, visa windows, contract terms, sprint planning and the ever-popular "days since the incident" counters. The total-days figure is unambiguous; business days excludes weekends and is what most deadlines actually mean — note it doesn't skip public holidays, which vary by country, so subtract those manually when precision matters.
Calendar math looks simple and hides traps: the "same date next month" problem when starting on the 31st, leap years, and time zones when times are involved. This tool works purely on calendar dates (no time-of-day), which sidesteps the timezone class of bugs entirely.
FAQ
Is the end date included?
The day count is the difference (start-to-end exclusive): Jan 1 → Jan 2 is 1 day. Add 1 manually if you count both endpoints, e.g. a 2-day conference on the same dates.
Can dates be in either order?
Yes — the tool reports the absolute duration regardless of which box holds the earlier date.