Date Difference Calculator
Calculate the difference between two dates in days, weeks, months, and working days.
About This Tool
The Date Calculator computes the exact difference between two dates in days, weeks, working days, months, and years. It also lets you add or subtract a number of days, weeks, or months from any date to find a target date.
Working days are counted as Monday through Friday, excluding weekends. The tool uses JavaScript's native Date API and runs entirely in your browser — no data is sent to any server.
How to Use
- Select the From date and the To date.
- Click Calculate to see the difference in days, weeks, working days, months, and years.
- Click the ⇄ button to swap the two dates if needed.
- To add or subtract time from a date, use the offset section at the bottom.
Use Cases
Project managers calculate the number of working days between a kickoff and deadline. HR teams compute notice periods and probationary end dates. Freelancers invoice clients based on the number of days worked. Students count down days to an exam or graduation. Event planners calculate how far in the future a date is for booking venues and suppliers.
FAQ
- Are public holidays excluded from working days? — No. Working days count Monday–Friday only; public holidays are not excluded since they vary by country.
- Can I calculate a date in the past? — Yes. Both past and future dates are supported. Swapping the From and To dates produces a negative difference.
- How are months counted? — Month differences are approximate (total days ÷ 30.44). For exact calendar month counts, use the years/months/days breakdown.