Date Interval Excluding Custom Holidays - Business Days Calculator

🇺🇸US Exclusive Use Cases

This custom-exclude calculator targets American small businesses and project teams with non-standard closure schedules:

• Small business scheduling: Shops and restaurants with their own holiday closure schedule beyond federal holidays
• Project team planning: Tech teams with company-specific shutdown weeks between Christmas and New Year
• State & local holidays: Businesses observing state-specific holidays like Patriots Day in Massachusetts or Pioneer Day in Utah
• Construction shut-downs: Building firms with weather-related or industry-specific closure days
• Freelancer billing: Independent contractors tracking billable days against their own working calendar

🌍US vs Global Calculation Differences

Custom holiday patterns differ sharply between the US and other countries:

• State-level variation: US states add their own holidays on top of federal — something rare in unitary European states
• Company shutdown weeks: American tech and finance firms often add year-end shutdowns that are not statutory holidays
• Floating holidays: Some US employers offer floating personal holidays that vary by employee
• Less statutory time off: Compared to EU countries with mandated 20–30 paid vacation days, US federal baseline is just 11 holidays, so custom exclusions matter more

⚠️Common Calculation Mistakes

Common mistakes: forgetting that a custom date falling on a weekend still counts as excluded (double-counting), entering dates in the wrong format, accidentally excluding start or end date when they should be included, and mixing up inclusive vs exclusive date boundaries. Always review your exclusion list for duplicates and weekend conflicts before calculating.

📐Tool Algorithm & Precision Explanation

The calculator computes working days by iterating through each date and applying exclusion rules in order:

• Weekend removal: Saturdays and Sundays excluded automatically
• Federal holiday removal: all 11 observed US federal holidays excluded by default
• Custom exclusion list: any dates you add are also removed from the count
• Deduplication: if a custom date falls on a weekend or federal holiday, it is not double-counted as excluded
• Inclusive counting: both start and end dates are included if they are working days

🎯US Federal Holiday & Workday Reference

The 11 federal holidays that are always excluded even before your custom list:

❓Frequently Asked Questions