Tool
Date Calculator — Add or Subtract Days
Pick a start date, choose to add or subtract, and enter the amount. The tool handles leap years and varying month lengths.
Month-end edge case
If you add one month to January 31, the result is February 28 (or 29 in a leap year) — the tool uses the JavaScript convention of rolling forward if the target day doesn't exist. If you need a strict month-end-to-month-end calculation, add 30 days instead.
Frequently asked questions
What is 30 days from today?
Use the tool — enter today's date, add 30 days. The exact result depends on the month, since some months have 28, 30, or 31 days.
Does it handle leap years?
Yes. February 29 is included in leap years and rolls correctly when you cross year boundaries.