Date Add / Subtract Calculator
Add or subtract a number of days from a date and see the resulting date with its weekday. Counting is by calendar day, so a negative number goes backwards, and month ends, year ends and leap years are handled by the date itself, so treat the output as a reference date.
How to use
- Pick a start date and enter the number of days; use a negative number, such as -30, to go back.
- The result shows the new date as YYYY-MM-DD together with its weekday.
- For a deadline 90 days out, enter 90 instead of counting months by hand.
FAQ
Are these calendar days or business days?
Calendar days. Weekends and holidays are included, so if the result lands on a weekend you need to roll it forward yourself. The result is an estimate; the contract governs the actual deadline.
Does it handle 29 February?
Yes. Dates are handled by the system calendar, so adding one day to 29 February gives 1 March, never 30 February.
Can it show the gap between two dates?
No. This shifts one date only; for a difference, use the workday counter or a dedicated date-difference tool.
Further reading