Written and maintained by DeadlineDaysReviewed on July 29, 2026
Choose the calculator that matches the decision you need to make, then keep its calendar assumptions visible with the result.
Count business days between two dates by country, excluding weekends, public holidays, and custom company holidays.
Find a date after 10, 30, or any number of workdays, or subtract business days from a deadline.
Calculate Net 30, Net 45, Net 60, EOM, calendar-day, or business-day invoice payment deadlines with weekend and holiday adjustments.
Plan SLA response deadlines with business hours, time zones, public holidays, and calendar-hour modes.
Estimate ship dates, delivery windows, and shipping calendar dates with order cutoff time, handling time, transit days, and weekend rules.
Find pay dates and assign one calculated payroll cutoff to a selected processing checkpoint, with business-day adjustments.
Calculate how many working days, work days, business days, and work hours are in a month or year by country.
View public holidays by country, region, and year, with source notes for national, regional, bank, school, optional, and observed holidays.
| Calculators | Decision | Inputs used | Output |
|---|---|---|---|
| Business Days Calculator: Count Workdays by Country | How many working days are in this date range? | Start and end dates · Country and holidays · Non-working days | Counted business days |
| Add Business Days Calculator: Add or Subtract Workdays | What date is a set number of workdays before or after this one? | Start date · Business-day amount · Calendar rules | Result date |
| Net 30 & Invoice Due Date Calculator | When is an invoice due under Net or EOM terms? | Invoice date · Payment term · Adjustment rule | Adjusted due date |
| SLA Deadline Calculator | When does a service commitment expire? | Start date and time · SLA duration · Business hours and time zone | SLA deadline |
| Shipping Date Calculator: Estimate Ship & Delivery Dates | When can an order ship and arrive? | Order and cutoff time · Handling and transit time · Origin and destination calendars | Ship and delivery dates |
| Payroll Cutoff Date Calculator | What payroll cutoff supports this pay date? | Pay period · Pay-date rule · Cutoff buffer | Pay and cutoff dates |
| Working Days in a Month Calculator | How much working capacity is in a month or year? | Month or year · Country · Work hours and holidays | Working days and hours |
| Public Holidays by Country and Region | Which public holidays affect this plan? | Country · Year · Non-working days | Holiday calendar |
Review South Korea's 2026 substitute-holiday baseline, the later Labor Day rule change, and a practical method for counting business days.
Compare Net 30 and Net 60 payment terms, clarify calendar-day and business-day wording, and calculate invoice due dates with weekend and holiday rules.
Reproduce a business-day count by separating start inclusion, end inclusion, weekends, verified holiday scope, and reverse-range handling.
Test business-window deadlines, verified holiday pauses, after-hours starts, and DST ambiguity without claiming instant conversion.
Validate an estimated ship and delivery window with warehouse, origin, destination, and carrier calendars instead of one merged holiday list.
Review the July 28, 2026 API-to-official-calendar comparison, including verified snapshots, mismatches, incomplete regional scope, and unsupported behavior.
Separate a negotiated invoice due date from EU and UK statutory late-payment triggers, with dated examples and primary-law scope checks.
Plan around official 2027 US federal observed dates and Singapore public holidays without treating either list as a universal employer closure calendar.