Date Diff

Days between two dates.

A free date calculator: find the days, weeks, months and a years-months-days breakdown between two dates (plus business days), compute an age and the days to the next birthday, and add or subtract days / weeks / months / years from a date. It all runs locally in your browser.

How to use

1. On the difference tab, pick a start and end date.
2. Read the days / weeks / months, the years-months-days breakdown and the business-day count.
3. Switch to the age or add/subtract tabs for those calculations.

FAQ

Does the day count include both endpoints?

It shows the number of whole days between the two dates (the difference), not an inclusive count; e.g. Jun 1 to Jun 3 is 2 days.

Are time zones considered?

It aligns to local calendar dates at midnight and compares dates only — no specific times or time zones — so results stay stable and intuitive.

Are my dates uploaded?

No. All calculations happen locally in your browser.

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