Add or subtract dates
Add or subtract time from a chosen date.
- 1Add input
- 2Adjust settings
- 3Get your result
Tool input and files are processed in this browser without being uploaded.
Before you start
Add years and months first, clamp to the final valid day of the destination month, then add days. This is calendar arithmetic, not a maintained holiday or business-day service.
How to use this tool
- Enter the date (yyyy-mm-dd) for add or subtract dates.
- Review Years, Months, Days before selecting “Calculate date”.
- Review the Date result, then use the available copy or download controls.
Supported inputs and limits
Pasted text is limited to 1 MiB; review the result before using it.
Worked example
Example input
2024-01-31
Example options
{
"months": 1
}Example output
2024-02-29
When something does not work
Check the input unit, calendar date and IANA time zone. A skipped daylight-saving time has no matching instant; a repeated time requires an explicit earlier/later choice.
Frequently asked questions
Are my files uploaded?
No. Files and tool input are processed in your browser. Moving around the site can keep a temporary workspace in the same tab. Refreshing or closing the tab clears it, so download results you want to keep.
What should I check in this result?
Add years and months first, clamp to the final valid day of the destination month, then add days. This is calendar arithmetic, not a maintained holiday or business-day service.
Documentation & further reading
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