How to use this calculator
Choose one of three modes using the tabs at the top. In “Days Between” mode, pick a start and end date to see the exact difference in days, weeks, months, and years, plus how many of those are business days. In “Add/Subtract Days” mode, enter a starting date and a number of days, weeks, or months to add or subtract to find the resulting date. In “Countdown” mode, pick any future date to see how much time remains.
Use the quick presets to load common scenarios instantly, like counting down to a holiday or finding the end of the year.
Common date reference periods
| Period | Calendar Days | Business Days |
|---|---|---|
| 1 week | 7 | 5 |
| 2 weeks | 14 | 10 |
| 30 days | 30 | ~22 |
| 60 days | 60 | ~44 |
| 90 days | 90 | ~66 |
| 6 months | ~182 | ~130 |
| 1 year | 365 | ~261 |
Frequently asked questions
How do you calculate the number of days between two dates?
Subtract the earlier date from the later date, accounting for varying month lengths and leap years. This calculator handles all of that automatically, including showing the result in days, weeks, months, and years.
What is the difference between calendar days and business days?
Calendar days include every day, weekdays, weekends, and holidays. Business days (also called working days) only count Monday through Friday, excluding weekends. For example, one calendar week is 7 days, but only 5 business days.
How do you add business days to a date?
Count forward from the start date but skip Saturdays and Sundays. For example, adding 5 business days to a Monday gives you the following Monday. This calculator can do the counting for you with the “Skip weekends” option.
How many business days are in a year?
A typical year has 260 to 262 business days (52 weeks times 5 weekdays), depending on which days January 1 and December 31 fall on. Public holidays can reduce the count by 10 to 12 additional days.
Does this calculator account for leap years?
Yes. The calculator correctly handles leap years when computing the number of days between dates or when adding and subtracting days. A leap year occurs every 4 years (with exceptions for century years not divisible by 400), adding February 29 to the calendar.