Date Difference Calculator
Days, weeks and months between dates
100% Private & In-Browser
Processed locally using client-side JavaScript. Your files and data never touch any server.
Instant & Unlimited
No registration, no waiting queues, and no limits on file conversions or generations.
What is Date Difference Calculator?
The Date Difference Calculator measures the exact duration between two dates in years, months, and days — plus total weeks and days — using true calendar arithmetic. Useful for tenancy lengths, project timelines, notice periods, and any countdown that must be legally or contractually exact.
How to use Date Difference Calculator
Pick the start and end dates.
The tool counts the full calendar span, handling leap years and varying month lengths.
Read the result as years/months/days and as total days or weeks.
Optionally include or exclude the end day, depending on your convention.
- Calendar-exact breakdown in years, months, and days
- Total days and weeks for payroll-style counting
- Leap-year aware, including February 29 edge cases
- Instant results computed locally — dates never leave your device
- Contract and tenancy durations where the day count must be exact.
- Project planning: elapsed time between milestones in calendar terms.
- Personal milestones — exactly how long until (or since) an event.
Frequently Asked Questions
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