Business Days, Working Hours & Deadline Calculator
Calculate working days between dates or add business days to forecast project milestones.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. No data is ever transmitted across the network.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
How to Use Business Days, Working Hours & Deadline Calculator
Choose between calculating days between two dates or adding business days to a start date.
Choose a 5-day (Mon-Fri) or 6-day (Mon-Sat) workweek.
Instantly see the total business days, weekend days, and billable work hours.
Frequently Asked Questions
Does this calculator exclude weekends?
Yes, it automatically excludes Saturdays and Sundays (or only Sundays if 6-day workweek is enabled).
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