> For the complete documentation index, see [llms.txt](https://doc.duaer.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doc.duaer.com/build/edit-fields.md).

# Change fields with Edit Fields in Duaer

In Duaer, Edit Fields (Set) adds or replaces fields on each item. Use it when you only change a few fields, instead of writing Code.
## Edit fields one by one

1. Search for Edit Fields and connect it after the previous node.
2. Leave Mode on Manual Mapping.
3. Under Fields to Set, add a row: the name on the left, the value on the right. The value can be an expression, such as {{ $now.toISO() }}.
4. Turn on Include Other Input Fields when the old fields should stay.
5. Select Execute step and check the new fields on the output.

JSON mode replaces the item with the JSON you write, instead of adding fields one by one. Refer to [Transform data with expressions in Duaer](/code/expressions.md).
## Questions

### Does Edit Fields in Duaer drop the incoming fields?

Yes, by default. The output is only what you list under Fields to Set. Turn on Include Other Input Fields to keep the incoming fields too.