Date Add / Subtract Calculator
Add or subtract any number of days, weeks, months, or years from a date and see the resulting day instantly.
Enter a date to start
Pick a start date and the result will appear here.
When to use it
Use this calculator to find delivery deadlines, contract end dates, medical follow-ups, or any future date that depends on adding or subtracting a fixed period from a reference date.
Frequently asked questions
Can I add weeks, months, or years?
Yes. Pick the unit and the calculator updates instantly.
Does this include the start date?
Yes. Adding 0 days returns the start date itself. Adding 1 day returns the next day.
Does it handle leap years?
Yes. Adding 1 year to Feb 29 returns Feb 28 of the next year; the calculator uses real calendar logic.
What about end-of-month edge cases?
Adding months keeps the day-of-month when possible. If the target month is shorter, the result clamps to the last day of that month.