Does this account for leap years?

Yes — since it works with actual calendar dates rather than a fixed 365-day year, leap years are handled automatically.

Can I calculate a date in the past by subtracting days?

Yes — enter a negative number of days to add to move backwards from your starting date.

Date Calculator

Calculate the number of days, weeks, and remaining days between two dates, or add/subtract days from a date to find a new one.

Mode

Start dateEnd date

How It Works

Days between two dates

The calculator counts the exact number of calendar days between your start and end dates, then breaks that total down into whole weeks plus remaining days.

Adding or subtracting days

Enter a starting date and a number of days to add (or a negative number to subtract) to find the resulting date, correctly handling month and year rollovers.

Example Calculation

From January 1 to January 11 is 10 days — exactly 1 week and 3 days. Adding 10 days to January 25 lands on February 4.

Common Mistakes

Forgetting whether to count the start date, end date, both, or neither — this calculator counts the difference in calendar days between the two dates (exclusive of double-counting either endpoint).
Not accounting for leap years when calculating dates far apart by hand.

Frequently Asked Questions

Does this account for leap years?: Yes — since it works with actual calendar dates rather than a fixed 365-day year, leap years are handled automatically.
Can I calculate a date in the past by subtracting days?: Yes — enter a negative number of days to add to move backwards from your starting date.