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Free Date Difference & Business Days Calculator Online
Date Difference & Business Days Calculator separates calendar days, weekdays, weekends and business days with an explicit inclusive or exclusive convention.
Business Days CalculatorWeekdays Between DatesCalendar Days CalculatorCustom Holiday Calculator
Interactive Date Difference & Business Days Calculator Workspace
Process your files or inputs directly in your browser. Many workflows run locally; features that need network data or a service are identified on their tool page.
At a glance
Date Difference & Business Days Calculator — Date Difference & Business Days Calculator separates calendar days, weekdays, weekends and business days with an explicit inclusive or exclusive convention.
Free for the core workflow, no account required. The calculation is performed locally in the browser from the values you enter.
About Date Difference & Business Days Calculator
Date Difference & Business Days Calculator separates calendar days, weekdays, weekends and business days with an explicit inclusive or exclusive convention.
Add custom holiday dates to model a specific work calendar. The calculator reports each component so the result can be audited rather than treated as an unexplained day count. Date math is trickier than it looks: months have different lengths, leap years add February 29, and daylight-saving transitions can make "24 hours later" land on a different wall-clock time. The calculator handles the calendar correctly so you do not have to. Calculator results depend on the inputs, units, assumptions, formulas and reference date or rate where applicable. Confirm units and assumptions, compare the result with a known example when possible, and verify current external rates or rules.
Primary objective: Finds date differences and performs date addition/subtraction with calendar-aware calculations.
Privacy assurance: The calculation is performed locally in the browser from the values you enter.
How to Use Date Difference & Business Days Calculator
- Enter the start and end dates.
- Choose inclusive or exclusive counting.
- Add custom holiday dates when they should be excluded from business-day totals.
- Review calendar days, weekdays, weekends, holidays and business days separately.
Key Use Cases & Applications
- Deadline planning
- Project scheduling
- Working-day calculations
- Holiday-aware delivery estimates
- Counting exact days between contract signing and a deadline.
- Planning project timelines in business days, excluding company holidays.
Frequently Asked Questions
Does it count weekends?
Yes. Weekend days are reported separately and excluded from the business-day total under the standard Monday-Friday convention.
Can I add holidays?
Yes. Enter custom holiday dates in YYYY-MM-DD format.
What does inclusive mean?
Inclusive counting treats both the start and end dates as counted dates; exclusive counting measures the elapsed interval.
Does it count the start date, the end date, or both?
The calculator counts exclusive of the start date by default (Jan 1 to Jan 2 = 1 day). For project planning, be explicit about whether deliverable day counts — that one-day ambiguity causes real scheduling arguments.
How are leap years handled?
Correctly: February 29 exists in years divisible by 4, except century years not divisible by 400. Date libraries handle this; manual spreadsheet math often does not.
Can I exclude weekends and holidays?
Yes — business-day mode skips Saturdays and Sundays, and you can add custom holiday dates for your country or company.