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Count working days (Mon–Fri) between two dates, or add/subtract business days. Leap-year and month-length correct.
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Counts business days (Monday–Friday) between two dates, or adds/subtracts a number of business days to a starting date. Leap years, month lengths, and year boundaries are all handled correctly.
Deadlines, SLAs, and shipping estimates are usually quoted in business days, but calendar-date math is full of traps: weekends land in the middle, months have different lengths, and leap years shift February. This tool computes all of that on a UTC-based calendar so results never depend on your timezone.
This tool is part of the DevStackIO platform — a collection of free online developer tools from DevStackIO. Browse more free developer resources on DevStackIO.
Project managers setting deadlines, shippers and logistics teams quoting lead times, HR and payroll teams computing notice periods, and anyone whose contract mentions 'business days'.
Pick 'Days between dates' or 'Add / subtract days'
Enter the start date (and end date, or the number of business days)
Use a negative number to subtract business days
Read the result: business days, calendar days, and weekend days — or the resulting date with its weekday
Jan 1 → Jan 31, 2024: 22 business days (31 calendar days, 9 weekend days)Jan 5 (Fri) + 1 business day → Jan 8 (Mon)Mar 1, 2024 − 3 business days → Feb 27 (Tue), crossing a leap-day FebruaryInvoice dated 2024-11-01 + 30 business days → 2024-12-13Q: Does it handle public holidays? A: No
holiday calendars differ by country and even by state. Subtract them yourself, or treat the result as the legal maximum.
Q: Is the result different around daylight-saving changes? A: No
all arithmetic is done on UTC calendar days, which have no DST gaps.
Q: What if I enter the end date before the start date?
A: You get a negative business-day count, which is the signed distance between the dates.
Q: How do I count calendar days instead?
A: Use the Date Calculator's 'difference' mode, which shows total days plus years/months/days.
Authoritative specifications, standards, and in-depth reading for Business Days Calculator.
Business days (Mon–Fri, start excluded)
22
30 calendar days total · 8 weekend days · from 2026-10-12 (Monday)
Counts Monday–Friday only. Public-holiday calendars vary by country and are not assumed — subtract them yourself. Leap years and month lengths are handled via the Gregorian calendar. Runs locally.
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