JSONL ↔ JSON Converter
Convert JSON Lines to a JSON array and back again.
JSONL input
Drop a file here
Drop a .jsonl or .json file
JSON output
About the JSONL ↔ JSON Converter
Turn a JSONL / NDJSON file into a proper JSON array for tools that expect one, or flatten a JSON array (optionally nested under a key) back into streaming JSON Lines for fine-tuning, BigQuery or log pipelines.
Examples
JSONL to array
{"id":1}
{"id":2}Output
[
{ "id": 1 },
{ "id": 2 }
]Keyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Version 1.0.0 · Updated 2026-08-14 · Runs entirely in your browser