Days Between Dates Calculator

Date & TimeLast updated: August 17, 2026

The number of days between two dates underpins contract terms, interest and rent calculations, project planning, visa applications, and event countdowns. Because months run 28 to 31 days and leap years get in the way, counting by hand goes wrong easily; this calculator gives the exact answer straight from the calendar.

Once you pick a start and an end date, you see the total number of days; the equivalent in weeks, months, and years-months-days; and the number of business days (Monday to Friday) and weekend days in the interval. The business-day count only excludes weekends — public holidays are not deducted. Even if you enter the dates in reverse order, the calculator still returns the correct difference.

The first day of the interval. This day is included in the count; the end day is not.
Today's date is used by default.

Formula

Total days = End date − Start date (in calendar days)
Weeks = Total days ÷ 7 (the remainder is shown in days)
Business days = the number of Mondays through Fridays in the interval
Weekend days = Total days − Business days

The count includes the start day and excludes the end day (from the 17th to the 20th is 3 days). If you want both ends included, add 1 to the result; rent and interest calculations generally use the difference method applied here.

How to Calculate

  1. Pick the start date (the first day of the interval).
  2. Pick the end date — it defaults to today.
  3. Read the total days, the week equivalent, and the years-months-days breakdown in the results section.
  4. Check the business-day and weekend counts, remembering that public holidays are not deducted.

Worked Examples

From New Year's Day to today

There are 228 days (32 weeks 4 days) between January 1, 2026 and August 17, 2026. Of these, 162 are weekdays and 66 are weekend days. In years, months, and days the difference is 7 months 16 days.

Total days: 228 days · In weeks: 32 weeks 4 days · In years, months, and days: 7 months 16 days

How many days are left in the year?

From August 17, 2026 to December 31, 2026 there are 136 days (19 weeks 3 days); 98 of them are business days and 38 are weekend days. This is how you can see the working time left for your year-end targets.

Total days: 136 days · In weeks: 19 weeks 3 days · In years, months, and days: 4 months 14 days

The length of a university degree

A course that starts on September 1, 2023 and ends on June 19, 2026 runs 1,022 days (exactly 146 weeks), which corresponds to 2 years 9 months 18 days. The interval contains 730 business days and 292 weekend days.

Total days: 1,022 days · In weeks: 146 weeks · In years, months, and days: 2 years 9 months 18 days

Frequently Asked Questions

Are the start and end days included in the count?
The calculator returns the difference between the two dates: the start day is included and the end day is not. From the 17th to the 20th of a month, for example, is 3 days. If you want to count both ends (calendar days rather than nights), add 1 to the result.
Are public holidays deducted from the business-day count?
No. The business-day count is found by excluding Saturdays and Sundays only. Public and religious holidays are not deducted, so for anything that depends on official working days you have to subtract those holidays separately.
What happens if I enter the dates in the wrong order?
Nothing breaks. If the end date comes before the start date, the calculator swaps them automatically and shows the absolute value of the difference; the result is always positive.
Why can the month figure differ from the years-months-days value?
The 'Total months' row gives the number of completed months (7 for an interval of 7 months 16 days, for instance). The years-months-days row splits the same span into calendar units. Because months run 28 to 31 days, values expressed in months are approximate.
Are leap years taken into account?
Yes. The calculation runs on the real calendar, so February 29 is counted in any interval that contains it. An interval covering the whole of 2024, for example, comes to 366 days.
Can I use it to count hotel nights?
Yes — the number of nights in hotel and rental calculations equals the difference in days between the check-in and check-out dates. A guest who arrives on the 17th and leaves on the 20th stays 3 nights, which is exactly the value this calculator returns.