Calculator
Date difference calculator
Calculate total days and calendar difference between two dates. Data is processed only in your browser, and the page explains the formula and limitations of the result.
Reviewed: 3 August 2026Processed locally
Calculator
Enter data
A start date and an end date. Fields marked with an asterisk are required.
How to use the calculator
- Enter the required data: a start date and an end date.
- Check the values and select “Calculate”.
- Review the primary result and the detailed calculation components.
Calculation details
Formula and calculation method
Total days are the UTC calendar-date difference; years and months are then subtracted in calendar terms.
Worked example
From 1 January to 31 January, 30 days pass, equal to 4 complete weeks and 2 days.
Limitations
- The result excludes the starting day and does not consider times, time zones or non-Gregorian calendars.
Sources
Engine version: 1.0 · Last reviewed: 3 August 2026
Frequently asked questions
Is the entered data sent to a server?
No. The calculation runs locally in your browser and the values are not saved by default.
Is the result definitive?
Not always. The result excludes the starting day and does not consider times, time zones or non-Gregorian calendars.