How to use
- Choose a tab: Days Between, Add / Subtract, Business Days, D-Day or Year Info.
- Pick your dates or enter a number, then click Calculate where a button is shown.
- Read the result and use the copy button to copy it.
The date calculator has five tabs, each for a common question.
Days Between takes a start and end date and shows the total number of days between them, plus a breakdown in years, months and days. The result is always positive, so the order of the two dates does not matter.
Add / Subtract starts from a date and adds or subtracts an amount in days, weeks, months or years. The answer is shown as a date together with the day of the week. When you add months, month lengths vary, so the result follows standard calendar rules for shorter months.
Business Days counts the working days between two dates, treating Saturday and Sunday as non-working days. Public holidays are not taken into account, so subtract them yourself if they apply.
D-Day lets you name an event and pick a target date. It shows a countdown such as D-10 before the date, D-Day on the day and D+5 afterwards, along with a live timer of the remaining days, hours, minutes and seconds that ticks every second.
Year Info takes a year and shows how many ISO weeks it has, how many days it has, and whether it is a leap year.
Dates are entered with your browser's date picker and the calculations run on your device. Nothing is uploaded.
FAQ
Does the order of the two dates matter?
No. Days Between and Business Days both show the absolute difference, so earlier and later dates can be entered in either field.
Does Business Days exclude public holidays?
No. It skips Saturdays and Sundays only. Holidays are not included.
What does D+ mean in the D-Day counter?
D+ followed by a number means the target date has passed by that many days. D- means days remaining, and D-Day means the date is today.
What does Year Info show?
The number of ISO weeks in the year, the number of days, and whether the year is a leap year.