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Calculate the exact number of days, weeks, months, and years between two dates. Handles leap years and varying month lengths correctly.
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Calculates the exact number of days, weeks, months, and years between two dates. Handles leap years, varying month lengths, and date ordering correctly. Uses UTC for day-accurate differences.
Date differences are needed for project planning, age calculation, deadline tracking, and historical analysis. Manual calculation is error-prone due to leap years and month-length variations.
This tool is part of the DevStackIO platform — a collection of free online developer tools from DevStackIO. Browse more free developer resources on DevStackIO.
Project managers, event planners, HR professionals, historians, students, and anyone needing precise date intervals.
Enter the start date (first field)
Enter the end date (second field)
The tool shows days, weeks, months (approx), and years (approx)
2024-01-01, 2024-12-312024-02-28, 2024-03-012023-01-01, 2024-01-01Does this include both start and end dates?
The day count is exclusive (end - start). Add 1 for inclusive count.
How are months/years calculated?
Approximate: months = year diff × 12 + month diff; years = year diff.
What about time zones?
The tool uses UTC dates for consistency.
Authoritative specifications, standards, and in-depth reading for Days Between Dates Calculator.
Days
365
Weeks
52.14
Months (approx.)
11
Years (approx.)
0
2024-01-01 → 2024-12-31 (inclusive: 366 days)
Uses UTC dates for day-accurate differences. Leap years and varying month lengths handled correctly. Runs locally.
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