Business Days Calculator
Count business days between dates, or add or subtract business days from a start date. Optional US federal holiday exclusion.
Formula
Business days exclude weekends (Saturday and Sunday) and optionally US federal observed holidays using OPM rules.
Assumptions
- Weekends are Saturday and Sunday.
- Federal holidays follow published OPM observance rules; schedules may change.
- Holiday table requires annual review when rules change.
Limitations
- State and local holidays are not included.
- Verify critical deadlines with official sources.
Worked example
Mon Jan 5 to Fri Jan 9, 2026
5 business days when both start and end are included and holidays are excluded.
Frequently asked questions
Which holidays are included?
US federal holidays only, using standard observed-date rules. State, local, and employer-specific closures are not included.
Can I include weekends?
Yes. Turn off the exclude-weekends option to count all days except any excluded federal holidays.
Last reviewed: 2026-07-23
Category: Date & Time
Results are provided for informational purposes only and may not reflect real-world policies, fees, or individual circumstances.
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