About NDJSON
This tool converts NDJSON (newline-delimited JSON, also called JSON Lines or .jsonl) into a JSON array, and back. NDJSON stores one JSON object per line and is common for logs, streaming and big-data exports. It runs in your browser.
How NDJSON to JSON works
How to use it
- Choose the direction (NDJSON → array, or array → NDJSON).
- Paste your data.
- Copy the converted output.
How it works
NDJSON → array parses each non-empty line as JSON and collects them into one array. Array → NDJSON writes each element on its own line. Invalid lines are reported so you can fix them.
Common uses
- Convert NDJSON to a JSON array
- Split a JSON array into NDJSON
- Process log exports
- Prepare data for streaming APIs
- Work with .jsonl files
- Inspect JSON Lines data
- Migrate data formats
- Validate line-delimited JSON
Frequently asked questions
What is NDJSON?
Newline-delimited JSON — one JSON object per line (JSON Lines/.jsonl).
How do I convert it to an array?
Paste the NDJSON and use the NDJSON → array direction.
Can I go the other way?
Yes — array → NDJSON splits an array into lines.
Is my data uploaded?
No — it converts in your browser.
What if a line is invalid?
The tool reports the error so you can fix it.
Why use NDJSON?
It streams and appends easily, line by line.
Is it free?
Yes — completely free with no sign-up.