What does this tool do?
Paste newline-delimited JSON (NDJSON) below to convert it into a single JSON array. Everything runs locally using JavaScript in your browser — nothing you paste or upload is ever sent to a server.
How to use this tool
- Paste your ndjson input into the left-hand box.
- Click Convert to JSON.
- Copy the json output from the right-hand box.
Frequently asked questions
What is NDJSON?
Newline-delimited JSON, where each line of the file is its own complete, standalone JSON value — commonly used for log files and streaming data.
What happens if one line has invalid JSON?
The tool reports exactly which line failed to parse and why, so you can fix that line without guessing.
Are blank lines allowed?
Yes — empty lines are skipped automatically.