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How to Calculate Future or Past Dates
Formula
This date calculator adds or subtracts days and weeks from a starting day to find the resulting day. Enter a starting day-of-year and the number of days or weeks to add.
It is useful for project planning, deadline tracking, and scheduling tasks a specific number of days in the future or past.
Common use cases:
- Project deadline calculations
- Countdown planning for events
- Scheduling recurring tasks
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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