Days Between Dates Calculator
Count how many days there are between two dates — useful for deadlines, countdowns, ages, notice periods and project planning. It also gives weeks, months and weekdays.
How to use the Days Between Dates Calculator
- Choose the start date.
- Choose the end date.
- Decide whether to count the end date as a full day.
How it works
Both dates are converted to calendar days and subtracted. By default the count excludes the end date (Monday to Friday is 4 days); choose “include the end date” to count both (5 days). The years-months-days breakdown follows the calendar, so it accounts for months of different lengths and leap years.
The weekday count includes Monday to Friday only. It does not subtract public holidays, which vary by country and state.
Days in each month
| Month | Days | Month | Days |
|---|---|---|---|
| January | 31 | July | 31 |
| February | 28 (29 in leap years) | August | 31 |
| March | 31 | September | 30 |
| April | 30 | October | 31 |
| May | 31 | November | 30 |
| June | 30 | December | 31 |
Frequently asked questions
How many days are in a year?
365 days, or 366 in a leap year (every 4 years, except century years not divisible by 400).
How do I count business days?
Count only Monday to Friday. The calculator does this automatically but does not remove public holidays.
Should I include the end date?
For durations (how long until), exclude it. For counting days of an event that includes both the first and last day, include it.
How many weeks are in a year?
52 weeks and 1 day (52 weeks and 2 days in a leap year).