Date Difference counts the exact time between any two dates — in years, months and days, and as a total number of days. Deadlines, tenures, project ages, days left for an exam — if the question is 'how long between', this is the tool.
Does it count both the start and end day?
It counts the elapsed time between the dates — the standard difference, like a subtraction. If you need an inclusive count for a booking or leave (counting both the first and last day), add 1 to the total days.
Can I count the days remaining until a future date?
Yes — enter today as the start and the future date as the end. The total-days figure is your countdown, and the years/months/days form shows it in calendar terms.
Do I need to sign up or install anything?
No. The Date Difference is completely free, needs no account and nothing to install — it runs in your browser, and anything you type stays on your device.