How to Calculate Days Between Two Dates (Free)

To find the number of days between two dates, subtract the earlier date from the later one — or skip the calendar math and use the free date difference calculator, which counts the exact days, weeks, and months between any two dates and handles leap years for you. Here's how it works and what to watch for.

Count days between two dates

Enter a start and end date in the Date Difference Calculator and it returns the span in days, weeks, and months instantly. The order doesn't matter — it uses the absolute difference — so you can't get a negative result.

Inclusive vs exclusive counting

One common gotcha: do you count both the start and end day, or just the gap between them? The calculator measures the span (end minus start). If you need to include both endpoints — say, counting event days — add one to the result.

Business days and countdowns

For working days, a rough estimate is 5/7 of the total, minus public holidays. For "how many days until" a deadline, set the end date to your target and read the day count. To add or subtract days from a date instead, use the Date Calculator.

Bottom line

Subtract the earlier date from the later — or let the Date Difference Calculator do it exactly, leap years included. To find your exact age, the Age Calculator uses the same math.