Why use this calculator
Quickly determine the exact number of days between any two dates. Useful for project planning, tracking deadlines, and calculating durations for contracts or events.
How to use it
Enter your start date and end date using the year, month, and day fields. The calculator instantly shows the difference in days, weeks, months, and approximate business days.
The formula
Days = End Date - Start Date; Weeks = Days / 7; Business Days = Full Weeks x 5 + min(Remaining Days, 5)
Worked examples
From January 1, 2024 to December 31, 2024
365 days, 52.1 weeks, 11 months, ~261 business days
From March 15, 2024 to June 15, 2024
92 days, 13.1 weeks, 3 months, ~66 business days
When people use it
- Project timeline planning and deadline tracking
- Calculating contract or lease durations
- Determining age or time elapsed between events
- Planning vacations and counting working days
Tips
- Business days are approximate and do not account for public holidays.
- The calculator handles negative differences if the end date is before the start date.
- Month calculations are based on calendar months, not 30-day periods.
- Use this to verify delivery timelines or payment due dates.
Questions people ask
- Does this account for leap years?
- Yes, the calculator uses standard date arithmetic which correctly handles leap years and varying month lengths.
- Are business days exact?
- Business days are approximate, counting 5 days per week. Public holidays and regional variations are not included.
- Can I calculate dates in the past?
- Yes, you can enter any start and end dates. If the end date is before the start date, the result will show a negative number of days.