Can I subtract days instead of adding?

Yes. Enter a negative number in the Days field (for example, -14) to go back in time from the start date.

Does the calculator account for leap years?

Yes. The JavaScript Date object handles leap years automatically, so adding days across February 29 works correctly.

What is the maximum number of days I can add?

There is no practical limit. You can add millions of days if needed; the JavaScript date engine handles large values without overflow.

Is the start date itself counted as day 1?

No. Adding 1 day to January 1 returns January 2, not January 1. Day counting is exclusive of the start date, which is the standard convention.

What date format is used for the result?

Results are displayed in a long, unambiguous format (for example, Wednesday, June 25, 2025) so there is no confusion between month-first and day-first conventions.

What date is 90 days from today?

Click "Use today" to set the start date, then press the +90d button; the result appears at once. The same buttons cover 7, 14, 30, 60, 180 and 365 days.

Does it skip weekends and holidays?

No. It counts calendar days, which is how most "within 30 days" deadlines are written. To count only working days, use the Business Days Calculator.

Is 3 months the same as 90 days?

Not always. Three calendar months run 89 to 92 days depending on the months. From March 1, 2027, adding 90 days gives May 30, while 3 months later is June 1. Check which one your contract or notice uses.

Add Days To Date

Enter a start date and a number of days to instantly see the resulting date after adding or subtracting those days.

Pick a start date, enter the number of days and click Calculate; use a negative number to count back.

Date & Days

Start Date

Days to Add (negative to subtract)

Quick Add

Enter a start date and number of days, then click Calculate.

Copied!

Quick answer

Pick a start date, enter the number of days and click Calculate; use a negative number to count back. The start date is day 0, so 1 day after January 1 is January 2. Leap years are handled for you.

Examples

Start date	Days	Result
January 1, 2027	+7	Friday, January 8, 2027
January 1, 2027	+30	Sunday, January 31, 2027
January 1, 2027	+60	Tuesday, March 2, 2027
January 1, 2027	+90	Thursday, April 1, 2027
January 1, 2027	+180	Wednesday, June 30, 2027
January 1, 2027	−30	Wednesday, December 2, 2026

Pick a date and add days.

Summary

Enter a start date and a number of days to instantly see the resulting date after adding or subtracting those days.

How it works

Enter or pick your start date using the date input.
Type the number of days to add (use a negative number to subtract).
Click "Calculate" to see the resulting date.
The result shows the full date, the day of the week, and the distance from today.
Click "Copy Result" to copy the resulting date to your clipboard.

Use cases

Find a deadline that is 30, 60, or 90 days from a contract start date.
Calculate a delivery or shipping date by adding estimated transit days.
Determine what date falls a certain number of days before an event.
Quickly figure out the day of the week for a future or past date.
Count forward from today to plan project milestones.
Verify payment due dates by adding net-30 or net-60 day terms.

Frequently Asked Questions

Last updated: 2026-05-28 · Reviewed by Nham Vu