Days Between Dates Calculator
Find how many days, weeks and months separate two dates, with or without counting the end date.
How to use the Days Between Dates Calculator
- Pick the start date.
- Pick the end date.
- Tick Include the end date (add 1 day) if it applies.
- Press Calculate. The result updates automatically as you type.
About the Days Between Dates Calculator
Counting days by hand across months of different lengths and leap years is error-prone. This days calculator gives the exact count for project timelines, pregnancy or recovery tracking, rental periods, interest accrual, travel stays and anniversaries.
By default the start date is counted and the end date is not, which is how most durations work: from Monday to Tuesday is 1 day. Tick "Include the end date" when both days count, such as the number of days of a conference or a hotel-free vacation day count.
Formula
days = (end date − start date) in days, + 1 if the end date is included
Weeks = ⌊days ÷ 7⌋ with the remainder shown as days. Weekdays are counted day by day from the start date, treating Saturday and Sunday as weekend days. Years and months are counted on the calendar, so they follow the real month lengths.
Example calculation
Using the default values:
- Start date = 2026-01-01
- End date = 2026-10-12
the calculator returns:
- Days between: 284 days
- Weeks and days: 40 weeks, 4 days
- Years, months and days: 0 years, 9 months, 11 days
- Weekdays (Mon–Fri): 202
- Weekend days: 82
- Hours: 6,816
Frequently asked questions
How many days are there from January 1 to October 12, 2026?
There are 284 days, or 285 if you include October 12 itself.
Should I include the end date?
Include it when you are counting days on which something happens (for example a 3-day festival from Friday to Sunday). Leave it off when you are measuring elapsed time.
Are leap years taken into account?
Yes. Every date is placed on the real calendar, so February 29 is counted in leap years.
How do I count only business days?
The weekday result excludes Saturdays and Sundays. For holidays as well, use the Business Days Calculator.
Last updated: · Category: Time & Date calculators