Date and time
Date difference calculator
Find the time between two dates in days, weeks, months, and years. You can also add days to a date or see how long until an event.
Calculate the time between two dates
Weekdays exclude Saturdays and Sundays; holidays are not excluded.
Weekdays exclude Saturdays and Sundays; holidays are not excluded.
How days are counted
Choose whether to measure elapsed time or count the first day of the period as well.
Standard
Counts from the day after the earlier date through the later date. From January 1 to January 2, for example, 1 day has passed.
Inclusive
Counts both the first and last day. January 1 to January 2 is 2 days. Reversing the dates gives the same number, with a message explaining which date comes first.
Weekdays
Counts Monday through Friday. Saturdays and Sundays are skipped; holidays are not excluded.
How to calculate months between two dates
A complete month ends on the same day of the following month. If that day does not exist, the last day of the month is used. Later months still use the original day as a reference: January 31 to March 30, 2026 is 1 month and 30 days, because the second month is not complete until March 31. February 28 to March 31, 2026 is 1 month and 3 days.
January 15, 2025 to March 20, 2026 is 14 months and 5 days, which can also be written as 1 year, 2 months, and 5 days. Starting on February 29 can make the two results differ. February 29, 2024 to March 28, 2025 is 12 months and 28 days; the thirteenth month ends on March 29. Counting years first takes you to February 28, 2025, then one more month takes you to March 28. That gives a result of 1 year and 1 month.
How to calculate weeks between two dates
Each week is 7 days. January 1 to March 2, 2026 is 60 days: 8 complete weeks and 4 days left over. This result includes Saturdays and Sundays, even when you choose weekdays as the main result.
January 15 to September 30, 2026 is 258 days: 36 weeks and 6 days, or 8 months and 15 days. Counting the first day too gives 259 days, or exactly 37 weeks. Inclusive counting changes the day total and its conversion to weeks; results in months and years always use standard counting.
Before using the result as a deadline
Legal, employment, tax, and contractual deadlines may follow specific counting rules. Check which days count and which holidays are excluded before using the result.
Frequently asked questions
How do I calculate the difference between two dates in days?
Enter the start and end dates to see how many days are between them. Choose Weekdays if you only want to count Monday through Friday.
Is the start day counted when calculating days between dates?
Standard counting starts on the day after the earlier date and includes the later date, even if you enter them in reverse order. January 1 to January 2 is therefore 1 day. Choose Inclusive to count the first day too, giving 2 days.
What is the difference between calendar days and weekdays?
Calendar days include every day of the week. Weekdays count Monday through Friday, including any holidays that fall on those days.
How do I calculate the date 30 days from now?
Open Add or subtract, click Today for the start date, choose Add, and enter 30 as the amount. Select Days to see the resulting date and day of the week.
How do I calculate 30 weekdays after a date?
In Add or subtract, choose your start date, select Add, and enter 30. Set the unit to Weekdays to skip Saturdays and Sundays.
Does the calculator exclude holidays?
No. A holiday that falls Monday through Friday still counts as a weekday.
How are complete months counted between dates?
Each month is measured from the day of the earlier date to the same day in a later month. If that day does not exist, the last day of that month is used. January 15, 2025 to March 20, 2026 is 14 complete months and 5 days. Choosing Inclusive does not change the result in months.
Why not divide days by 30 to find months?
Months have different lengths. For example, January 31 to February 28, 2026 counts as one complete month, even though only 28 days have passed.
How do I find complete weeks and remaining days?
Every group of 7 days makes one week, and any days left over are shown separately. For example, 60 days is 8 weeks and 4 days. This result uses calendar days and follows your choice of standard or inclusive counting.
Can I use it for legal or employment deadlines?
It can help you count the days. Before using the result as a deadline, check which days count and which holidays are excluded under the relevant rules or contract.