Date Calculator
Find the number of days between two dates, or add and subtract days, weeks, months, and years from any date. Includes a days-until countdown.
Total Days
0 days
Years / Months / Days
0y 0m 0d
Full Weeks
0 weeks
Breakdown
Same day
Frequently Asked Questions
How many days are between two dates?
Enter a start date and an end date in the Date Difference mode. The calculator counts the exact number of calendar days between them using millisecond-accurate arithmetic, then also breaks the span down into years, months, days, and full weeks. Toggle 'Include end day' to count both the start and end dates in the total.
How do I add or subtract days from a date?
Switch to the Add/Subtract mode, enter your starting date, choose an amount and unit (Days, Weeks, Months, or Years), then pick Add or Subtract. The calculator applies proper calendar math — adding months accounts for different month lengths, and adding years handles leap years — so the result is always a valid calendar date.
How do I count down the days until an event?
Use Date Difference mode with today as the start date and your event date as the end date. The result shows the total days remaining. You can also use Add/Subtract mode in reverse: set the event as your start date and subtract today's date to see how many days away it is.