Business Days Calculator
Count business days between two dates, excluding weekends and public holidays.
How business days are calculated
This calculator counts every day in a date range that isn't a weekend or a national public holiday for the country you choose. It's the calculation behind project deadlines, delivery estimates, payroll processing windows and SLA commitments — the kind of "5 business days" promise that only means something once weekends and holidays are correctly excluded. The date range is inclusive of both the start and end date, and if the range spans more than one calendar year, public holidays are looked up for each year involved so nothing gets missed at a year boundary.
Weekends alone remove roughly 2 days out of every 7 from a calendar-day span, and public holidays typically remove another 8–12 days per year depending on the country — so a naive calendar-day count can overstate the actual working time available by 30% or more. This calculator's own public holiday data is the same dataset used by the Public Holidays calculator for 60+ countries. For the total calendar-day span between two dates without excluding weekends or holidays, see the Date Difference calculator, and for a running countdown to a fixed future date, see the Countdown calculator.
Frequently asked questions
- What counts as a business day?
- Any calendar day that is not a Saturday, a Sunday, or a national public holiday for the country you select.
- Are the start and end dates both included?
- Yes. The range is inclusive — if the start and end date are the same weekday, that single day is counted.
- How are public holidays determined?
- From the same national public holiday data used by the public holidays calculator on this site. A holiday that falls on a weekend is not double-counted.
- Can I calculate business days across multiple years?
- Yes — the calculator fetches public holidays for every year the date range spans.
- Can I use this in my own app?
- Yes — every calculator on Stupidly Clever has a matching REST API and MCP tool that runs the same underlying logic.
- How do I add a number of business days to a date?
- Enter your start date as both the start and end date, then adjust the end date forward until the business day count matches your target. For example, to find "15 business days from today", step the end date forward until the calculator reads 15.
- What is the difference between business days and working days?
- They mean the same thing in most contexts: weekdays (Monday–Friday) excluding public holidays. Some industries count Saturdays as working days — for those calculations, you would need to manually exclude only Sundays and public holidays.