Date Calculator
Two everyday jobs: how far apart are two dates, and what date is N days from now.
Days between two dates
Difference
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Calendar days
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Weekdays (Mon–Fri)
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Weeks
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Add or subtract days
Result date
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Counting days correctly
The classic off-by-one: Monday to Friday is 4 days apart but 5 days inclusive. This calculator reports the difference (end minus start) — the convention used for deadlines, interest accrual and project durations. If your context counts both endpoints ("a 5-day festival, Monday through Friday"), add one.
Weekdays vs. business days
The weekday count above excludes Saturdays and Sundays but not public holidays, which vary by country and year. For legal or payroll deadlines defined in "business days", subtract any holidays in the window manually — and note some jurisdictions have their own counting rules for when the clock starts.
Everyday uses
- Notice periods: 30/60/90 days from a letter's date — use the add-days tool.
- Returns & warranties: "within 30 days of purchase" — count from the receipt date.
- Pregnancy & medical: appointments and milestones are set in exact day/week counts.
- Project planning: the weekday count gives you actual working time between milestones.
Frequently asked questions
Does the calculator handle leap years?
Yes — all arithmetic uses real calendar dates, so February 29 is counted in leap years and skipped otherwise.
Why does "difference" show years and months too?
For long spans, "2 years, 3 months, 12 days" is more meaningful than "834 days". Both are shown; use whichever your situation calls for.
Are time zones an issue?
Dates are treated as plain calendar dates in your local zone, so no. Only if you're coordinating a deadline across continents does the zone matter — in that case the contract or authority setting the deadline defines it.