Convert CSV to JSON Lines
Convert CSV rows into newline-delimited JSON (JSONL/NDJSON)
CSV Input
Try a sample:
Drop a CSV file here or
Only the first file is used if multiple are dropped.
The request is made directly from your browser. No proxy is used.
JSON Lines
JSON Lines output will appear here...
Options
CSV Format
Conversion
How to Use This Tool
Use this tool when you need one JSON record per line instead of a single JSON array. JSON Lines (also called JSONL or NDJSON) is a common format for logs, data pipelines, and streaming imports.
The converter accepts pasted CSV text, local files, or a CSV URL. It runs client-side in your browser and shows parse warnings when Papa Parse can recover from malformed rows.
- Step 1 — Paste CSV, drop a file, or fetch a URL in the CSV Input panel.
- Step 2 — Configure CSV parsing options like delimiter, headers, and dynamic types.
- Step 3 — Copy or save the JSON Lines output (
.jsonl) for your downstream tool.
FAQ
3 questionsDoes this CSV to JSON Lines converter upload my data?
No. The conversion runs entirely in your browser. Your CSV data stays on your device unless you choose to fetch a remote URL directly from your browser.
What does the output look like?
Each CSV row becomes one minified JSON value on its own line. With headers enabled, each line is a JSON object. With headers disabled, each line is a JSON array.
Can I parse numbers and booleans automatically?
Yes. Enable Dynamic types to have values like 42, 3.14, true, and false emitted as JSON numbers and booleans instead of strings.