Date Difference Calculator
Calculate the exact time difference between two dates.
Why Use This Calculator?
Calculate the exact duration between two dates, providing the difference in years, months, weeks, and days. Useful for project planning, age calculation, or countdowns.
Recommended Workflow
Select Start Date
Choose the beginning date from the calendar.
Select End Date
Choose the concluding date.
Review Duration
See the exact time difference broken down into multiple units.
Common Mistakes to Avoid
- •Miscalculating leap years when trying to do the math manually.
- •Confusing inclusive vs exclusive date boundaries.
What to do next?
Frequently Asked Questions
Does this calculator include the end date?
Typically, date difference calculators count the days between dates, excluding the final day unless specified.
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Duration
The measurable length of time that something continues or exists between a start and end point.
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Leap Year
A year containing one additional day (February 29th) to keep the calendar year synchronized with the astronomical year.