# Add or Subtract Days from a Date

> Find the date a set number of days, weeks, months or years before or after another.

To add or subtract time from a date, enter the starting date, an amount and a unit. The result shows the new date with its day of the week. Enable working days to skip weekends, which is how notice periods and delivery windows are usually counted.

**URL:** https://convertto.tech/t/date-add-subtract
**Category:** Date & Time Tools (https://convertto.tech/c/date-time-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Enter or paste your start date.
2. Choose the direction.
3. Set the amount.
4. Choose the unit.
5. Turn "Count working days only" on or off as needed.
6. The result appears immediately — copy or download it.

## FAQ

### What happens when I add a month to 31 January?

The result clamps to the last valid day of the target month — 28 or 29 February. This matches how spreadsheets and most date libraries behave, and avoids silently rolling over into March.

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