Date Difference Calculator

Calculate the number of days, weeks, and remainder days between two dates. Free and private, right in your browser.

Pick a start date and an end date to instantly see how many days, weeks, or months separate them, useful for tracking deadlines, calculating someone's age, figuring out how long a project ran, or counting down to an event.

How to use it

  1. Pick your start date
  2. Pick your end date
  3. Read the day, week, and month totals instantly

Frequently asked questions

Does it count the start date, the end date, or both?
By default it counts full days between the two dates (end minus start). If you need the start day included, add 1 to the result. The tool shows both the raw difference and common variants like inclusive counts.
Can I calculate a date that's a certain number of days in the future or past?
Yes. Enter one known date and the number of days to add or subtract, and it works out the resulting calendar date, which is handy for deadlines, due dates, or countdowns.
Does it handle leap years and different month lengths correctly?
Yes, it calculates using actual calendar dates, so February 29th and varying month lengths (28–31 days) are all accounted for automatically, no manual counting needed.