Date Difference Calculator
Calculate the time between two dates in years, months, days, weeks and hours, or add and subtract durations — with optional business days. Free, in your browser.
Everything runs in your browser — no dates are uploaded or stored.
About Date Difference Calculator
The Date Difference Calculator measures the exact time between any two dates, broken down into years, months, weeks, days, hours and minutes. It also reports the total number of days, weeks, hours and minutes between them, plus the count of business days with weekends excluded.
The calculator counts full calendar years and months first, then the remaining days, so month lengths and leap years are handled correctly. A second mode lets you add or subtract a duration — years, months, weeks, days, hours or minutes — from a base date instead.
Use it to count days until a deadline, work out how long a project ran, verify contract periods or check the gap between two events. Everything runs in your browser, so no dates are uploaded or stored anywhere.
How to use Date Difference Calculator
- Choose the calculation mode: “Difference between dates” or “Add or subtract”.
- For a difference, pick a start date and an end date (with optional times), or click “Use today” to fill in the current date.
- Tick “Include the end day in the count” if the final day should count as a full day.
- For the add/subtract mode, pick a base date, choose Add or Subtract, and enter the years, months, weeks, days, hours or minutes to apply.
- Read the full breakdown instantly — exact duration, total days, weeks, hours, minutes and business days.