Can I calculate a date far in the past or future?

Yes, both the add/subtract and difference tools work with any valid calendar date.

Date Calculator

Q: Does this account for leap years?

Yes, all date math uses real calendar dates, so leap years and varying month lengths are handled automatically.

Add, subtract or find the difference between dates

Add or Subtract Days

Start Date

Days

Operation

Result Date —

Difference Between Two Dates

From Date

To Date

Total Days0

Weeks0

Years, Months, Days—

What is the Date Calculator?

The Date Calculator adds or subtracts a number of days from a date, and finds the exact gap between two dates — in total days, weeks, and a years/months/days breakdown. It's useful for deadlines, project planning, contracts and event countdowns.

How to Use It

To add or subtract days: pick a start date, enter the number of days, choose Add or Subtract, and the result date appears instantly.
To find the gap between two dates: enter a "From" and "To" date in the second section for a full breakdown.

Example

A 90-day payment term starting January 15 ends on April 15. The gap between January 1 and April 15 is 104 days — or 3 months and 14 days.

Frequently Asked Questions

Yes, all date math is based on actual calendar dates, so leap years and varying month lengths are handled automatically.

Yes, both tools work with any valid calendar date, past or future.