How to Calculate Business Days Between Dates (2026)
The number of working days between two dates is rarely the same as the number of calendar days — weekends and public holidays come out of the count. The Business Days Calculator counts the working days between any start and end date, removes weekends and holidays automatically, and shows the full breakdown of calendar days, weekends, and holidays excluded. Here’s how business-day counting works and where the details matter.
What Are Business Days?
Business days, also called working days, are the days of the week when most businesses operate — typically Monday through Friday, excluding weekends and public holidays. The standard business week runs five days, so a project that takes ten business days spans about two calendar weeks. Counting business days is essential for contract deadlines, shipping estimates, HR leave calculations, and project scheduling. Unlike calendar days, business days exclude the non-working periods that would inflate a timeline estimate.
How to Use Our Business Days Calculator
- Open the Business Days Calculator and select a Start Date and End Date.
- Optionally click Add Holiday to exclude specific dates from the count.
- View the Business Day Count along with the breakdown of total calendar days, weekends excluded, and holidays excluded.
- Switch to Add Mode to calculate what date falls N business days from a start date.
Example Business Day Calculations
| Start | End | Calendar Days | Business Days |
|---|---|---|---|
| Mon, Jun 1 | Fri, Jun 5 | 5 | 5 |
| Mon, Jun 1 | Mon, Jun 8 | 8 | 6 |
| Mon, Jun 1 | Fri, Jun 12 | 12 | 10 |
| Mon, Dec 21 | Mon, Jan 4 | 15 | 10 (with holidays) |
Common Use Cases
- Project deadlines — estimate how many working days a deliverable actually needs, excluding weekends.
- Contract and legal timelines — many agreements specify deadlines in business days rather than calendar days.
- Shipping and delivery estimates — carriers often quote delivery in business days.
- HR and payroll — calculate working days for leave accrual, attendance tracking, and pay periods.
FAQ
What is a business day?
A business day is any day Monday through Friday that is not a public holiday. Saturday and Sunday are excluded. Different countries and industries may define business days differently, but Monday through Friday is the universal standard.
Does the calculator include the end date?
Yes. The end date is included in the count. For example, Monday to Friday inclusive counts as 5 business days.
Can I add custom holidays?
Yes. Click the Add Holiday button to include any dates you want excluded. Only weekdays are actually excluded — if you add a holiday that falls on a weekend, it has no effect since that day is already excluded.
What is the Add mode?
Add mode lets you enter a start date and a number of business days, then calculates the end date that falls that many working days later, skipping weekends and holidays automatically.
Do business days differ between countries?
Yes — the weekend is the same (Saturday/Sunday) but public holidays differ by country and even by state or province, so the same date range gives a different count in the UK, US, Canada, or Australia. See Working Days by Country for each one’s holidays.
Quoting a deadline in working days? Set your dates in the Business Days Calculator and pick the country so the right public holidays drop out — the per-country holiday lists are in Working Days by Country.