Date addition and subtraction calculation
Count days, months and years forward or backward from the specified date.
Date addition and subtraction calculation User manual
- Fill in the parameters or select the file according to the form, and check the unit and format first.
- January 31, 2026 plus 1 month, gets February 28, 2026.
- Click the processing button to view the results, you can copy or download and save.
Calculation method and processing rules
Use the UTC calendar operation; when the monthly or year estimate encounters a non-existing date, take the last day of the target month.
scope of use
Only the date of the Gregorian calendar is calculated, and the month is not fixed as 30 days, and there is no statutory working day.
Can I return to the original day if I add one month to add another month on January 31?
Not necessarily. Add one month to take the last day of February, and then reduce the day number used for this date for another month, so it may get January 28 or 29. This is the natural result of the truncation rule at the end of the month, not to add or subtract according to the fixed number of days.
Will the input content be saved on the server?
This tool handles input in the browser, and does not upload files or form content. Typing practice scores are only saved in the native browser.
Why may the result be different from other tools?
Only the date of the Gregorian calendar is calculated, and the month is not fixed as 30 days, and there is no statutory working day. Please compare the input unit, rounding method, applicable rules and data version first.