Web Toolkit

Date Difference Calculator

Count the days, weeks, months and business days between two dates.

Date range

Calculated on calendar dates in UTC, so daylight-saving changes cannot skew the result.

Private by design. Everything runs locally in your browser. Your input is never uploaded, logged or stored on a server.

Frequently asked questions

Should I include the end date?

It depends on what you are counting. Elapsed time excludes it; a duration such as a hotel stay or a notice period usually includes it. Both figures are shown.

How are business days counted?

Every day that is not a Saturday or Sunday within the range. Public holidays differ by country and are not deducted, so adjust manually if needed.

How are months calculated?

As a calendar breakdown of whole years, whole months and remaining days, not as a decimal. Months vary between 28 and 31 days, so a single decimal figure would be misleading.

Are leap years handled?

Yes. Ranges spanning 29 February include that day automatically.

About the Date Difference Calculator

Two dates, several valid answers — which is why date arithmetic causes so many off-by-one disputes in contracts and invoices.

Inclusive vs exclusive is the first choice. From the 1st to the 5th is 4 days if you count elapsed days, or 5 if you count the days themselves. Notice periods and rental terms usually mean the inclusive count; this tool shows both and lets you pick.

Business days excludes Saturdays and Sundays. Public holidays vary by country and are not deducted automatically, so subtract them yourself for a contractual deadline.

Months and years are shown as a calendar breakdown (for example 2 years, 3 months, 12 days) rather than as a decimal, because months have different lengths and any decimal answer would be an approximation.

Calculations run on calendar dates with no time component, so daylight-saving transitions cannot skew the result.

Related tools