About this tool
How many days until the deadline — and how many of those are actual working days? Date Duration Calculator answers both instantly. Pick a start and an end date and the tool breaks the span down every way you might need: total calendar days, weeks plus remaining days, an approximate months-and-days decomposition, and a count of weekdays versus weekend days. The working-day figure is the one project plans are made of, and it is computed properly by walking the range day by day rather than multiplying by five-sevenths, so partial weeks come out right. Inclusive and exclusive day counts are both shown, because from Monday to Friday is five days to a person and four to a subtraction. Spans where the end precedes the start are reported with a negative sign rather than an error. Everything updates live as you change the inputs, and there is no server involved: it is two date pickers and arithmetic, running locally. Use it for sprint planning, contract notice periods, visa day counting, warranty windows or settling arguments about how long ago something actually happened. If you need to convert timestamps rather than calendar dates, the timestamp converter is one click away in the same category.
How to use Date Duration Calculator
- Pick the start date and the end date.
- Read the breakdown: total days, weeks plus days, months plus days.
- Check the working-days count for the number that excludes weekends.
- Note the difference between the exclusive difference and the inclusive span count.
Frequently asked questions
Does the working-days count exclude public holidays?
No — it excludes Saturdays and Sundays only. Public holidays vary by country and employer, so subtract the holidays in your range from the working-day figure manually.
Is the end date included in the count?
Both figures are shown: the exclusive difference (end minus start) and the inclusive span, which counts both boundary days and is one larger.
How accurate is the months-and-days breakdown?
It is a calendar decomposition: whole months are counted by month boundaries, then the remainder in days. Because months vary in length, that is the only honest way to express it.
What happens if the end date is before the start date?
You get a negative duration with the same breakdowns, which is useful for 'how long ago' questions. Swap the dates if you want the positive span.