Date Difference Calculator
Calculate the gap between dates, including business days
What is Date Difference Calculator?
A date difference calculator reports the number of days, whole weeks, business days, and whole months between two dates, and can also project a date forward or backward by a given number of days. The business-day count excludes Saturdays and Sundays only. Calculation happens locally in your browser.
How to use Date Difference Calculator
- 1Pick a start date and an end date.
- 2Read the four totals: days, whole weeks, business days, and whole months.
- 3Enter a number of days below to project a date forward or backward, along with the day of the week it lands on.
Frequently asked questions
Does the business-day count exclude public holidays?+
No — it only skips Saturdays and Sundays. Holiday calendars vary by country and shift from year to year; mainland China, for instance, publishes its holiday and make-up working day schedule annually with no fixed pattern. If you need holiday-accurate figures, use a service that maintains a holiday calendar for your region.
How are whole months counted?+
By whether the same day of the month has been reached: 31 January to 28 February is not yet a full month, while 31 January to 1 March is. That matches how most contracts and billing periods work, but conventions differ between businesses, so confirm the rule before you rely on it for invoicing.
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