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Date Difference Calculator

Days between any two dates — deadlines, contracts, countdowns.

Contract terms, project deadlines, visa windows, warranty periods — half of adult life is counting days between dates. This calculator gives you the exact day count between any two dates, plus week and average-month equivalents and an approximate workday count for planning.

Why people use this

Contract terms, project deadlines, warranty windows, visa validity, countdowns to events. People use this whenever the question is "how many days between X and Y" — and the workday estimate makes it genuinely useful for planning, not just curiosity.

How it works

1. Pick the start date and end date.
2. The calculator computes the exact calendar-day difference.
3. Weeks and months are shown as conversions (months use the 30.44-day average).
4. Approximate workdays assume a standard 5-day week (~5/7 of all days).

Common questions

Does the count include the end date?

This calculator uses the standard convention: the difference between the two dates, so the start day is not counted but the end boundary is. For an inclusive count, add 1.

How are months computed?

As days divided by 30.44 — the average month length. Calendar months vary from 28 to 31 days, so for contract-grade "three calendar months" language, count month-by-month rather than by days.

Can it count backward to a past date?

Yes — if the end date is before the start date, the result is negative, telling you how many days ago that date was.

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