About this Business Days
In business, '10 days' usually means 2 weeks because weekends don't count. This calculator determines the exact number of working days (Monday through Friday) between a start and end date.
Who this calculator is for
- Project managers, operations teams, and office staff planning workday-based timelines.
- Anyone estimating notice periods, turnaround times, or delivery windows that skip weekends.
- Workers comparing calendar-day timelines with actual Monday-to-Friday schedules.
When to use it
- Estimate how many working days sit between a start date and a deadline.
- Convert a calendar range into a weekday-only count for payroll, HR, or project planning.
- Sanity-check shipping, onboarding, or approval windows before communicating timelines.
How to use this calculator
- Select the Start Date.
- Select the End Date.
- The calculator computes the number of Business Days (Mon-Fri) and Total Days.
Key assumptions
- Business days are defined here as Monday through Friday only.
- Source-dated holiday presets can exclude recognized weekday holidays, and manual excluded days remain editable.
- The count excludes the start date and includes the end date when the end date falls on a weekday.
Accuracy and testing
Review formula sources, default test cases, assumptions, unit handling, rounding rules, and changelog for this calculator.
How this calculator works
The algorithm starts from the selected start date, moves forward one day at a time until it reaches the end date, and counts only weekdays. That means it excludes the start date itself and includes the end date if that day is Monday through Friday.
Inputs explained
Dates
The range you want to measure. This tool excludes the start date and counts forward through the end date when that end date is a weekday.
Understanding your results
A 14-day calendar span often contains 10 business days, but the exact result follows this tool's weekday-only rule: start date excluded, end date included when applicable.
Example scenarios
One Week
Monday to the following Monday. Total Days: 7. Business Days: 5.
Weekend Span
Friday to Tuesday. Total Days: 4. Business Days: 2 (Monday, Tuesday).
Key Features
- Excludes Weekends
- Comparison with Total Days
- Project Planning Tool
Things to Keep in Mind
Holiday presets are source-dated planning references and may not include private, agency-specific, emergency, or local closures.
Tips & Best Practices
- Use a source-dated holiday preset when it matches your jurisdiction, then add manual excluded days for closures the preset does not cover.
- Useful for calculating shipping times or notice periods.
Glossary of Terms
- Business Day
- Any day other than Saturday, Sunday, or a legal holiday.
- Calendar Day
- Every day of the week, including weekends and holidays.