Date Difference Calculator

Pick two dates and instantly see the exact difference — years, months, days, total days, weeks and weekdays.

How long until the project deadline? How many days have you been together? Is the warranty still valid? Enter any two dates and this calculator breaks the gap down every way you might need it — calendar-precise years, months and days, plus total days, weeks and weekdays.

How the calculation works

Total days counts calendar days from the start date to the end date (end date minus start date, so Sep 1 to Sep 2 is 1 day). The years/months/days breakdown borrows from calendars the way people do: from Mar 31 to Apr 1 is 0 months and 1 day, not a full month. Weekdays count Monday through Friday only.

Common uses

Project management: time remaining to a milestone. HR: employee tenure. Anniversaries: days together. Warranties and returns: whether you are still inside the window. Contracts: notice periods. Enter today as the start and any future date as the end to get a live countdown.

Frequently asked questions

Does the count include both the start and end date?
No — total days is end minus start. If you want to include both first and last days (like hotel nights plus one), add 1 to the total.
Do the weekday counts skip public holidays?
No, they only skip Saturdays and Sundays. Federal holidays vary by year and country, so adjust manually if that matters.
What if I enter the dates backwards?
The calculator automatically swaps them and returns the positive interval.

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