Date & Business Day Calculator
Measure the signed number of calendar days and weekdays between two dates, with absolute days and week conversion alongside them.
Runs locally in your browser
Dates are compared as calendar dates in UTC. Weekdays exclude Saturday and Sunday but do not exclude public holidays. The end date is excluded.
Discuss a result
Write a short summary and review it before posting. Your tool inputs are never copied automatically.
What is the Date & Business Day Calculator?
Measure the signed number of calendar days and weekdays between two dates, with absolute days and week conversion alongside them.
How to use it
- 1Choose a start date and an end date.
- 2Read the signed day count and absolute difference.
- 3Reverse the dates if you want the opposite direction.
How it works
Both date-only values are normalized to UTC midnight. Calendar days use their millisecond difference divided by 86,400,000. Weekdays are counted one day at a time, excluding Saturdays and Sundays.
One week apart
January 1 to January 8 is seven elapsed calendar days. The end date itself is not counted as an extra day.
Limitations & notes
- The end date is excluded from the elapsed calendar count.
- Weekdays exclude weekends but do not account for public holidays or a custom workweek.
Frequently asked questions
How many business days are between two dates?
Count weekdays from the day after the start date through the end date. This tool does exactly that: from Monday, October 5, 2026 to Friday, October 9, 2026, it shows 4 weekdays (Tuesday through Friday). If you need to include the start day as a working day, add one when the start is a weekday. Public holidays are not removed, so subtract any that fall in the range.
Should I count the start date, the end date or both?
It depends on the question. Elapsed time, such as nights of a hotel stay or days until a deadline, excludes one end: January 1 to January 8 is 7 days. Inclusive counts, such as the number of days an event runs or a leave request covering both dates, add one: January 1 through January 8 is 8 days. This calculator reports elapsed days, so add 1 for an inclusive count.
How many weekdays are in a year?
A 365-day year has 52 full weeks plus one extra day, so it has 260 or 261 weekdays depending on which day the year starts. This tool shows 364 days and 260 weekdays from 2026-01-01 to 2026-12-31 because the start date itself is excluded. In the US, subtracting the 11 federal holidays gives about 249 to 250 working days for most full-time schedules.
Why does the result show a negative number?
The calculator keeps the direction of time. If the end date is earlier than the start date, days, weekdays and weeks are shown as negative values, for example −14 days, meaning the end date is two weeks before the start. The Absolute days figure removes the sign. This is useful for checking whether a deadline has already passed relative to today.
Do daylight saving changes or time zones affect the count?
No. Both dates are treated as calendar dates at UTC midnight, so a range that crosses a daylight saving change still counts whole days with no 23- or 25-hour error. Only valid dates are accepted, so an impossible date such as February 30 shows an error. Leap years are handled automatically: February 28 to March 1 is 2 days in 2028 and 1 day in 2026.
No directly related discussion yet.
Start a focused thread and share the question this tool helped you explore.
Ask the community about Date & Business Day Calculator