Business day calculator
Add working days to a date or count a range, with optional standard US federal holidays.
- 1Add input
- 2Adjust settings
- 3Get your result
Tool input and files are processed in this browser without being uploaded.
Before you start
Find a target date by adding working days, or count working days in a date range. Choose your workweek and either enter excluded dates yourself or apply the standard US federal holiday calendar.
How to use this tool
- Choose Add working days or Count between dates. Enter the start date and a working-day count or an end date.
- Choose your workweek, holiday calendar and any extra excluded dates in YYYY-MM-DD format.
- Calculate, review the target date or count, then copy it or download the JSON.
Supported inputs and limits
Use YYYY-MM-DD calendar dates in years 0001–9999, without time or zone. Addition excludes the start and zero keeps the original date; ranges include the start and optionally the end. Endpoint difference allows 36,600 days, so including both endpoints allows 36,601 dates.
Add 0–10,000 working days. At most 36,600 dates after the start are visited; if the target cannot be found, the whole calculation is refused. Exclusion text allows 60,000 UTF-8 bytes and 5,000 original date tokens; duplicates use token capacity but are deduplicated for counting. Active parameter values together allow 2 MiB.
The US federal preset requires a standard Monday–Friday workweek and calculation years 2000–2099; Juneteenth begins in 2021. Current recurring Friday/Monday observation rules do not predict future laws, regional Inauguration Day, state/employer holidays or one-off closures; supply extra dates manually.
The complete result retains every date actually excluded. Manual dates outside the period or on non-workdays are counted as ignored. Calculation stops after 10 seconds; cancellation or failure provides no partial result.
Worked example
Example input
2026-09-21
Example options
{"start":"2026-09-21","end":"2026-09-30","workdays":"1,2,3,4,5","includeEndDate":true,"holidays":"2026-09-28"}Example output
{
"startDate": "2026-09-21",
"endDate": "2026-09-30",
"includeEndDate": true,
"workdays": [
"Mon",
"Tue",
"Wed",
"Thu",
"Fri"
],
"calendarDays": 10,
"nonWorkdays": 2,
"excludedHolidays": 1,
"businessDays": 7,
"ignoredHolidays": 0,
"holidayCalendar": "manual",
"excludedHolidayDates": [
"2026-09-28"
]
}When something does not work
Check dates, active mode and workweek. The federal preset requires Monday–Friday and years 2000–2099. Check exclusion UTF-8 bytes and original token count. If the bounded scan cannot reach a target, review exclusions or reduce the range; retry from the same input after cancellation or timeout.
Frequently asked questions
Does this include the end date?
Yes by default. Turn off “Include end date” when the final date is a deadline rather than an available workday.
Are US federal holidays automatic?
Choose Standard US federal holidays to exclude recurring federal holidays and Friday/Monday observed dates for a Monday–Friday schedule. The calendar covers 2000–2099 and includes Juneteenth from 2021. Enter any state, employer or one-off closure dates yourself.
Is my input sent to a server?
No. Calculation runs in your browser. Temporary workspace data lasts in this tab only; save the result you need.
Documentation & further reading
Related tools
Timestamp converter
Convert integer Unix timestamps and known-offset dates, with UTC and IANA-zone display.
Time zones and UTC formatting
Resolve time zones and daylight-saving ambiguity, or format an instant in UTC.
Days between dates
Find out just how far apart two dates are.
Add or subtract dates
Add or subtract time from a chosen date.