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CSV to JSON Lines

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Convert CSV rows into JSON Lines (JSONL/NDJSON)

Paste CSV data to convert each row into its own JSON object, one per line (JSON Lines / NDJSON), with an option to treat the first row as a header. Runs entirely in your browser.

Lines: 2

JSON Lines
{"name":"Ada","role":"Engineer","active":"true"}
{"name":"Grace","role":"Scientist","active":"true"}

Everything on this page is processed in your browser. Nothing is uploaded.

What this tool does

JSON Lines is a common format for log files, streaming pipelines and bulk-import APIs: each line is a standalone, valid JSON value, so a consumer can process the file one line at a time without parsing the whole thing first. This tool parses CSV the same way a spreadsheet would, including quoted fields with embedded commas and quotes, then emits one JSON object per data row keyed by the header names, or one JSON array per row when there's no header to name the fields.

How to use it

  1. Paste CSV data, or load the example.
  2. Turn the header row toggle on if the first row holds column names.
  3. Copy the JSON Lines result.

Privacy

This tool runs entirely in your browser. Your input is never uploaded, stored or shared — closing the tab removes it.

Frequently asked questions

Is my CSV uploaded anywhere?
No. Parsing happens in JavaScript running in the page, so nothing you paste ever leaves your device.
What happens without a header row?
Each row becomes a plain JSON array of its cell values in order, since there are no column names to use as object keys.
How are quoted CSV fields handled?
Fields wrapped in double quotes, including ones containing commas, line breaks or escaped `""` quotes, are parsed the same way a spreadsheet application reads them.

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