Convert NDJSON to a JSON array
Paste NDJSON (one JSON value per line) and combine it into a single JSON array — handy for logs, exports and LLM datasets. Blank lines are skipped and an invalid line is reported by number. The result is saved privately in your account.
No sign-up needed — runs instantly in your browser.
How it works
- 1Paste your NDJSON / JSON Lines
- 2Choose the indentation, then press Run
- 3Download the JSON array or find it in your files
Frequently asked questions
- What is NDJSON?
- Newline-delimited JSON — one complete JSON value per line, the common format for logs and streaming data.
- What happens with a bad line?
- You get a clear error naming the line number that failed to parse, so you can fix it.
Related tools
Paste a JSON array and convert it to NDJSON — one compact JSON value per line. This is the de-facto format for logs, streaming exports and LLM training and evaluation datasets. The result is saved privately in your account.
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DeveloperPaste JSON to check whether it's valid. If it isn't, you'll see the exact error and where parsing failed; if it is, you get a quick report of its type, key count and nesting depth — saved privately in your account.
DeveloperPaste Base64 to decode it back to readable text. Both standard and URL-safe Base64 are accepted. The result is stored privately in your account.
Developer