Date Difference Calculator
Find the exact number of days, weeks, months, and years between any two dates — including business day counts.
Frequently Asked Questions
How do I calculate the number of days between two dates?
Select a start date and end date above, then click "Calculate Difference". The tool subtracts the earlier date from the later one in milliseconds and converts the result into days, weeks, months, and years — handling month-length variations and leap years automatically.
What is the difference between business days and calendar days?
Calendar days include every day — weekends and holidays included. Business days count only Monday through Friday. For example, a 14-calendar-day span starting on a Monday contains 10 business days. This distinction matters for delivery deadlines, payment terms, and legal notice periods.
How do I calculate a contract or notice period duration?
Enter your contract start date as "From Date" and your expected end or notice-period date as "To Date". The result shows the total duration broken down by calendar days and working days — practical for employment resignation notices, lease agreements, and software project timelines.