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How to Calculate Days Between Dates
Formula
To find the number of days between two dates, subtract the start day from the end day. If spanning multiple years, add 365 days per additional year.
This calculator also converts the result into weeks and approximate months for easy reference.
Common use cases:
- Calculating project duration
- Finding age in days
- Tracking time between events
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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