Calculate the number of days between two dates.
Pick a start date and an end date, then click Count Days. The calculator returns the number of calendar days between them, and tells you whether the end date comes after or before the start date if you enter them out of order.
Whether "the number of days" should include both endpoints depends entirely on what you're counting, and getting it wrong is a common source of off-by-one mistakes. Book a hotel from January 1 to January 5: that's 4 nights — the exclusive difference this calculator returns. But if you're counting how many calendar days the trip touches, including both the 1st and the 5th, that's 5 days. The same logic applies to notice periods, rental agreements, and trial periods: check whether the rule you're working with counts both ends or just the gap between them, and add 1 to this calculator's result if it does.
Days accumulate faster than the number suggests. Someone turns 10,000 days old at roughly 27 years and 4 months, and 30,000 days old at around 82 years — a way of marking a birthday that a plain age-in-years count doesn't capture. Enter a birth date as the start date and today as the end date to see the exact figure, useful for the classic "X days old" birthday milestone or just satisfying curiosity about a specific date range.
Useful for counting down to a deadline or event, checking how many days a rental, trial period, or notice period covers, or working out someone's age in days rather than years.
No, it counts the number of full days between the two dates (the difference), not an inclusive day count. For an inclusive count — for example, booking a hotel for both the arrival and departure date — add 1 to the result.
Yes. The calculator still shows the number of days between them and notes that the order is reversed.
No, it compares calendar dates only, not specific times, so time zones don't affect the result.
Yes — the calculator works from actual calendar dates, so any leap day (February 29) between your start and end date is automatically included in the count without any extra steps.