How do I calculate the number of days between two dates?

Enter both dates in the calculator and it instantly shows the difference in days, weeks, months, and years. The calculation accounts for varying month lengths and leap years.

How do I calculate business days between two dates?

This calculator shows both total days and business days (weekdays only, Monday-Friday). It excludes Saturdays and Sundays but does not account for holidays, which vary by country and region.

Does this calculator account for leap years?

Yes. The calculator correctly handles leap years when computing differences. Leap years occur every 4 years (with exceptions for century years not divisible by 400) and add February 29 to the calendar.

Date Difference Calculator

Find the exact duration between two dates in multiple units.

Start Date

End Date

Duration

—

Unit	Value
Total Days	—
Total Weeks	—
Total Months	—
Total Years	—
Business Days (Mon-Fri)	—
Weekend Days	—
Total Hours	—
Total Minutes	—

Understanding Date Differences

Calculating the difference between dates is more complex than it might seem because months have varying lengths (28-31 days), leap years add an extra day, and there's no universal definition of "one month" in days.

How Business Days Are Calculated

Business days (also called working days or weekdays) include Monday through Friday, excluding Saturday and Sunday. This calculator counts business days between your two dates. Note that it does not exclude public holidays, which vary by country, state, and organization.

Common Use Cases

Project planning: How many working days between start and deadline?

Contract terms: "Within 30 business days" — what's the actual end date?

Travel planning: How many days/weeks is my trip?

Pregnancy tracking: Weeks between dates for due date calculations

Event countdown: How many days until the wedding, graduation, or holiday?

Months and Years

The "total months" calculation divides the total days by 30.437 (the average month length). The "years, months, days" format uses calendar math — counting whole years, then whole months, then remaining days, accounting for the actual days in each month. This matches how humans naturally count durations.

Frequently Asked Questions

Enter both dates above. The calculator instantly shows the difference in days and every other unit. It correctly handles varying month lengths and leap years.

This calculator shows business days (weekdays, Mon-Fri) alongside total days. It excludes weekends but does not account for public holidays, which vary by location.

Yes. All calculations correctly handle leap years. Feb 29 exists in years divisible by 4 (except centuries not divisible by 400).

Yes! Use the "Add or Subtract Days" section below the main calculator. Enter a start date and the number of days to add (use negative numbers to subtract).