Business Days Calculator
Working days excluding holidays.
Uncheck to count only weekends as non-working days.
Business days
0days
Enter a start and end date.
What are business days?
Business days (working days) are the days between two dates on which work is actually done, typically excluding Saturdays and Sundays, and optionally public holidays. This is commonly used to estimate contract deadlines, project timelines, and document processing periods.
How it is calculated
The calculator walks day by day from the start date to the end date and counts days that are not Saturday or Sunday. When the holiday option is enabled, dates in the representative 2026 holiday list below are also excluded.
Business days = total days − weekend days − holiday days (if enabled)
2026 representative holidays
| Date | Holiday |
|---|---|
| Jan 1 | New Year's Day |
| Feb 16–18 | Seollal (Lunar New Year) |
| Mar 1 | Independence Movement Day |
| May 5 | Children's Day |
| May 24 | Buddha's Birthday |
| Jun 6 | Memorial Day |
| Aug 15 | Liberation Day |
| Sep 24–26 | Chuseok |
| Oct 3 | National Foundation Day |
| Oct 9 | Hangeul Day |
| Dec 25 | Christmas Day |
What's excluded — substitute holidays and this tool's limits
Business-day calculations typically exclude two things: recurring weekends and government-designated statutory holidays. Korea's substitute holiday system moves certain holidays (Seollal, Chuseok, Children's Day, etc.) to the next weekday when they overlap another holiday or a weekend, per annual government notice.
This calculator's code registers a fixed list of 14 representative 2026 holidays (HOLIDAYS_2026) and excludes those dates plus weekends while walking day by day. Since the list is fixed in advance, any substitute holiday announced later in the year is not automatically reflected, so results may differ by a day or more in years with substitute holidays.