Count the days, weeks, months and years between two dates.
Your dates stay on your device.
How do you calculate the difference between two dates?
The tool counts whole years between the dates, then the remaining months, then the remaining days, and also reports the total span in days and weeks, handling leap years automatically. The breakdown and total describe the same span differently. From 1 January 2025 to 13 June 2026 is 1 year, 5 months and 12 days, or 528 days.
Understanding your result
The breakdown and the total days describe the same span in different ways, useful for contracts, projects and milestones.
Formula and method
The tool counts whole years, then remaining months, then remaining days between the dates, and also reports the total in days and weeks. Leap years are handled automatically.
Assumptions and limitations
This tool measures the span between two calendar dates, not clock times, so it does not report hours, minutes or working days. It counts every calendar day, ignoring weekends and public holidays. Month and year figures depend on the exact dates involved, which is why the day total is often the clearer measure.
Worked example
From 1 January 2025 to 13 June 2026 is 1 year, 5 months and 12 days, or 528 days.
How to use this tool
- Pick a start date.
- Pick an end date.
- Press Calculate.
Common mistakes to avoid
- Swapping the dates — the tool always reports a positive span.
About the Date Difference Calculator
Measure the exact span between two dates in days, weeks, months and years.
Who should use this tool
Anyone tracking the gap between two calendar dates: project managers checking milestones, contract administrators counting notice periods, HR staff working out service length, students planning study timelines, or people simply curious how far apart two events sit. It suits anyone who needs both a plain-English breakdown and a precise day total.
Benefits
- Shows the same span two ways: a breakdown and a day total
- Handles leap years automatically so counts stay accurate
- Reports weeks alongside days for quick planning
- Gives instant results without sending anything to a server
Practical use cases
- Counting the notice period left on a contract
- Measuring how long a project has been running
- Working out length of service for records
- Checking the gap between two historical events
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Frequently asked questions
Does it include the end date?
The total counts the days elapsed between the two dates (the end date is the final day reached).
Why do the breakdown and the total number of days differ?
They describe the same span in different ways. Months and years vary in length, so the years-months-days breakdown depends on the exact dates involved, while the total is a simple count of every calendar day between them. Both are correct; the day total is just the more uniform measure.
Can it count only working days?
No. The calculator counts every calendar day in the span, including weekends and public holidays. It has no way of knowing your working pattern or which holidays apply in your region, so for business-day counts you would need a dedicated working-days tool instead.