Date Difference Calculator
Days, weeks, months and years between two dates — plus add or subtract time from a date.
Find days between two dates, or add and subtract days, weeks, months and years from any date. Get results in days, weeks, months and years, with correct month-length and leap-year handling.
Calendar: Gregorian, leap-year aware, month arithmetic clamped to valid days.
Difference between two dates
Add or subtract from a date
How to use the Date Difference Calculator
- Pick the two dates.
- Read the difference in days, weeks, months and years.
- Use the arithmetic mode to add or subtract time from a date.
Frequently asked questions
How do I count days between two dates?
Select both dates above and the tool shows total days instantly, including the breakdown in months and years.
Does it include the end date?
It counts the full 24-hour spans between the dates; for an inclusive count, add one day.
How does it handle leap years?
Leap days are counted correctly — February 29 is included in any range that covers it.
Can I add months to a date?
Yes — month arithmetic clamps to valid days (for example Jan 31 + 1 month = Feb 28 or 29).