Find the number of days between two dates, or calculate a new date by adding or subtracting whole calendar days. This free date calculator counts elapsed calendar days, complete seven-day weeks, the years/months/days interval, and Monday–Friday weekdays. Choose whether to count both the start and end dates. For a deadline or anniversary, switch modes and enter a positive or negative day offset. The calculation uses calendar dates rather than elapsed hours, so daylight-saving transitions do not accidentally add or subtract a day. No sign-up or payment is required.
## How many days are between two dates? Enter the start and end date. The default result counts the number of calendar-day boundaries between them: the starting date is excluded and the ending date is included. For example, January 1, 2024 to December 31, 2024 spans 365 elapsed days, even though 2024 has 366 calendar dates because it is a leap year. Select the inclusive option when you want to count both January 1 and December 31; in this case the result is 366 calendar dates. The tool also accepts dates in reverse order but reports the positive interval and tells you that the inputs were reversed.
## Calendar weeks, months and years. Complete seven-day weeks are calculated by dividing the counted days by seven and discarding any remainder. For the default 365-day interval, there are 52 complete seven-day weeks and one remaining day. The calculator separately shows the elapsed interval in completed calendar years, months and days, with month-end anniversaries clamped to a valid date. Those calendar values do not use average month lengths. Changing the inclusive checkbox changes the count of calendar dates, not the underlying elapsed years/months/days interval.
## Weekdays between two dates. The tool counts Monday, Tuesday, Wednesday, Thursday and Friday, excluding weekends. By default it excludes the starting calendar date and includes the ending calendar date. Between Friday, March 6, 2026 and Monday, March 9, 2026, the elapsed interval is three calendar days and contains one counted weekday, Monday. If you select inclusive counting, both Friday and Monday are included: four calendar dates and two weekdays. Saturdays and Sundays are not counted as weekdays, but national, regional and bank holidays are not excluded. Do not use this simple weekday count as a legally defined business-day deadline without checking local rules.
Elapsed calendar days, inclusive days, weekdays and date offsets
Elapsed days = |UTC date(end) − UTC date(start)| ÷ 86,400,000
Inclusive dates = Elapsed days + 1
Complete weeks = floor(Counted calendar days ÷ 7)
Weekdays = Monday–Friday dates in the counted interval (public holidays not excluded)
New date = Start date + Integer calendar-day offset
Inputs are Gregorian calendar dates without times. By default the start date is excluded and end date included for weekday counts; inclusive mode counts both. Month/year decomposition follows completed calendar anniversaries and does not use average-length months.
Find the number of days and weekdays from January 1, 2024 to December 31, 2024.
Result: 365 elapsed days, or 366 dates inclusive; 52 complete weeks plus one day, and 261 weekdays (262 inclusive), excluding public holidays.
Subtract the start calendar date from the end calendar date. The tool uses UTC date-only arithmetic to avoid daylight-saving shifts and returns the positive elapsed interval.
Not by default. The elapsed count excludes the start date and counts through the end date. Enable inclusive counting if you want both dates included.
There are 365 elapsed days, or 366 inclusive dates because 2024 is a leap year. The default weekday count is 261; including both dates makes it 262 weekdays before holiday exclusions.
The calculator counts Monday–Friday weekdays, but it does not exclude any public or bank holidays. Legally defined business days may require local holiday and cutoff rules.
Switch to Add or subtract days, select the starting date and enter 30. The tool counts calendar days, including weekends and holidays.
Enter a negative whole-number offset, such as -30, in the Add or subtract days mode.
February 29 is counted when it occurs. Adding one calendar day to February 28, 2024 returns February 29, 2024.
The tool normalizes the dates and returns the positive interval. It also indicates that the entered dates were reversed.