How long are 5 or 10 business days? Weekends, holidays and start dates
Calculate weekday baselines and identify when Korean or US holidays change a deadline.
A phrase such as “within five business days” does not always produce one universal deadline. You must know whether the start date counts and whether the rule excludes only weekends or also national, court, bank or company holidays.
Four calculation modes
UCALX can add or subtract business days, show a 5–10 business-day window, or count business days between dates. Weekends are excluded by default.
Check whether day zero counts
“Beginning the next day” excludes the triggering day; “including the filing date” includes it. Follow the governing document or ask the issuing organisation.
Korean public holidays
Korean government holidays are defined by current regulations. Labour Day and Constitution Day were incorporated into the government-holiday framework in 2026, so current rules matter.
US federal business days
For US federal work, OPM publishes the federal holiday and in-lieu-of schedule. State agencies, courts, banks and private businesses may follow different calendars.
Starting on the day after a Monday, five weekdays are Tuesday, Wednesday, Thursday, Friday and the following Monday. An applicable holiday in that span can move an official deadline later.
What to check
- Check whether the triggering date is included.
- Identify the country and organisation whose holidays apply.
- Check the deadline time and time zone.
- Verify court, tax, visa and financial deadlines with the responsible authority.
“Business day” has no single worldwide definition. The 2026 Korea and US holiday presets are sourced planning aids; the governing document and organisation’s calendar control a legal or contractual deadline. Outside 2026, only weekends are excluded.
Official sources checked
Standards can change. These links are provided so you can verify the current primary source.
Business Days Calculator: Add 5 or 10 Business Days
Apply the baseline above with your own dates and figures.