Calculate the exact number of days, weeks, months, years, and business days between two dates.
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A date difference calculator computes the temporal duration between two calendar dates. It provides breakdowns of total calendar days, full weeks, months, calendar years, and working business days (excluding Saturdays and Sundays).
\Delta t = \frac{t_2 - t_1}{86,400,000 \text{ ms/day}}Universal Time Coordinated (UTC) midnight timestamps are subtracted to avoid daylight saving shifts, and days of the week are evaluated to isolate Monday through Friday business days.
Scenario: Find working days between October 1, 2026 and October 15, 2026.
Total span: 14 calendar days.
Weekend days: 4 days (2 Saturdays, 2 Sundays).
Business days: 10 working days.
This calculator standardizes business days as Monday through Friday. Because national holidays differ across jurisdictions and companies, federal holidays are not automatically deducted.
Yes, the underlying calendar system uses Gregorian calendar standards for past and future centuries.
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Add or subtract days, weeks, months, and years from any date or calculate the exact duration between two dates.
Equivalent to 1 month (4 full weeks).
21
Mon – Fri9
Sat & Sun