How do you calculate days between two dates?
Subtract the start date from the end date. The date calculator determines the difference automatically in days, weeks, months and years.
Date Calculator
With the date calculator you can determine the period between two dates or add and subtract days, weeks, months and years from a date.
Result
Calculation
Date calculator – modes and notes
Calculate date range
Enter a start date and an end date to calculate the time span in years, months, weeks and days.
Add or subtract dates
From a base date you can add or subtract any combination of years, months, weeks and days.
Calculate workdays
The date calculator can also count how many Monday-to-Friday days fall within a period. Public holidays are not considered.
Free and no storage
The date calculator is free, requires no sign-up and does not store inputs. All calculations run server-side using real calendar rules including leap years.
Frequently asked questions about the date calculator
Is the start date included?
By default the start date is the reference point, but the end date is not counted as an additional full day. Example: 1 January to 2 January equals 1 day.
Can the end date be included?
Yes. Enable “Include end date” to count both boundary dates in the day total.
Are leap years considered?
Yes. The date calculator uses real calendar dates and handles leap years correctly.
How is 29 February handled?
29 February is treated as a valid date in leap years. For year calculations the result is clamped to the last valid day of the target month, e.g. 29 February 2028 plus 1 year = 28 February 2029.
What happens when adding one month to 31 January?
The result is clamped to the last valid day of the target month. Example: 31 January plus 1 month = 28 or 29 February.
How are workdays calculated?
All Mondays through Fridays in the selected period are counted. Saturday and Sunday count as weekend days.
Are public holidays subtracted from workdays?
No. Public holidays are not handled separately.
Can I add years, months, weeks and days at the same time?
Yes. You can combine multiple units. The calculator applies them in the order years, months, weeks and days.
Can I calculate an earlier date too?
Yes. If the end date is before the start date, the calculator still computes the difference and shows the direction.