> 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/tools/csv-to-json.md).

# CSV to JSON converter (free, no upload)

A free Duaer tool that turns each CSV row into a JSON object keyed by the header row. Optional number and boolean detection, GBK support, copy or download.

Interactive converter (runs in the browser, no upload): https://doc.duaer.com/tools/csv-to-json/

## How to use it

1. Drop a CSV file, or paste CSV and click "Convert".
2. Tick "Detect numbers and true / false" if you need typed values.
3. Click "Copy" or "Download .json".

## Conversion rules

- The first row holds field names; blanks become `column_2`, duplicates become `name_2`.
- Values stay strings by default so leading zeros in codes survive.
- Fully empty rows are skipped.

## Automate it in Duaer

In Duaer you rarely need JSON first: [Extract from File](/integrations/builtin/core-nodes/duaer-nodes-base.extractfromfile.md) › Extract From CSV already turns each row into an item, and later nodes read values with `{{ $json.fieldName }}`.
## Questions

### Is the output an array or one object per line?

The Duaer converter outputs one JSON array with an object per row, ready for a Code node or a request body.

### Will commas or line breaks inside cells break it?

No. The Duaer parser follows standard CSV quoting, so commas and line breaks inside quotes are kept.

## Related

- [Free file converters from Duaer](https://doc.duaer.com/tools.md)
- [CSV to Excel converter (free, no upload)](https://doc.duaer.com/tools/csv-to-excel.md)
- [Excel to CSV converter (UTF-8, no upload)](https://doc.duaer.com/tools/excel-to-csv.md)
- [JSON to CSV converter (nested JSON flattened)](https://doc.duaer.com/tools/json-to-csv.md)
- [Parse CSV text in Duaer, including GBK files](https://doc.duaer.com/snippets/parse-csv-in-code-node.md)