Days Between Dates — Calculate Exact Date Difference Free
Calculate days between two dates
Calculate the exact number of days, weeks, months, and working days between any two dates.
About Days Between Dates
A date difference calculator determines the exact number of days, weeks, months, and business days between any two dates. While rough mental estimates are easy, precise day counts are essential for deadlines, project planning, legal timelines, and personal milestones.
The tool counts calendar days (every day, including weekends) and business days (Monday–Friday only) separately. Business day counts are particularly valuable for project management, contract deadline tracking, payroll cycle calculations, and legal notice periods where "working days" have a specific meaning distinct from calendar days.
Common uses include counting down to an important date (a holiday, event, or deadline), determining how long ago something occurred, calculating the number of working days available to complete a project, verifying contract notice periods, and planning iterative work sprints.
The tool also expresses the result in weeks and months for convenient contextual reference. The swap button instantly reverses the two dates, useful when you know the end date and want to count backward. All calculations use JavaScript's native Date API with full support for leap years, varying month lengths, and any valid date in the Gregorian calendar. No data is stored or transmitted.
Frequently Asked Questions
What is the difference between calendar days and business days?
Calendar days count every day including weekends and public holidays. Business days count only weekdays (Monday–Friday), excluding weekends. The tool provides both counts.
Does the calculator account for leap years?
Yes. JavaScript's Date API correctly handles leap years in all date difference calculations.
Can I calculate the number of days until a future date?
Yes. Set the start date to today and the end date to any future date to get the exact number of days remaining.
What is the maximum date range supported?
The tool supports any dates within the valid JavaScript Date range — effectively any date from year 100 to year 9999.