Date Difference Calculator

Find the exact number of days, weeks, months, and years between two dates, or quickly add days to a date for deadlines and events.[web:614][web:615][web:618]

Mode
Between two dates
Today
2025-12-21
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What this date calculator does

Date‑difference tools are ideal for counting days until deadlines, tracking streaks, and planning travel or financial milestones by showing calendar time spans clearly.[web:614][web:618][web:624]

  • Calculate days between two dates with optional inclusive end‑day counting. [web:618][web:621]
  • Convert days to weeks and estimate years, months, and leftover days. [web:614][web:617]
  • Add or subtract a number of days, weeks, months, or years to find future or past dates. [web:615][web:632]
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How to calculate days between dates

To calculate days between two dates manually, convert each date to a serial day count, subtract the start from the end, then decide whether to include the final day in the total.[web:617][web:622][web:625]

Date difference tips for planning

  • Use inclusive counting when you want to know how many calendar days an event spans from start to finish.[web:618][web:621]
  • For business schedules, track working days separately since many date tools treat all calendar days equally by default.[web:624][web:630]
  • When adding months or years, watch for month‑end rollover, because calendars have different month lengths and leap years.[web:615][web:625]
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