Date Difference Calculator
Pick a start and end date to instantly see the total number of days between them, broken down into years, months and days — plus total weeks and business days. Everything updates live in your browser.
How to Use the Date Difference Calculator
- Choose a Start Date using the date picker.
- Choose an End Date using the date picker.
- The total days, year/month/day breakdown, total weeks and business days update instantly.
- It doesn't matter which date is earlier — the calculator automatically works out the difference either way.
Why Use This Tool?
How is the day count calculated?
The tool takes the two calendar dates you select and computes the exact number of full days between them, then converts that into total weeks. It also calculates a calendar-accurate years/months/days breakdown, so "1 year, 2 months, 5 days" reflects real calendar months rather than a rough average.
What counts as a "business day" here?
Business days are counted as any Monday through Friday between your two dates, excluding Saturdays and Sundays. This is a simple weekday count and does not subtract public holidays, since holiday calendars vary widely by country and region.
Does it handle leap years correctly?
Yes. Because the calculation is based on real JavaScript date objects rather than a fixed average day count, leap years and varying month lengths are automatically accounted for in both the total day count and the year/month/day breakdown.
What can I use this for?
This calculator is handy for figuring out project timelines, contract durations, rental periods, how many days until a deadline, or simply how much time has passed since an event. Pair it with the Days Until Countdown Tool for a live countdown to a future date.