Developer Tools
JSON Lines Formatter
Format, normalize, or convert pasted JSON Lines / NDJSON records locally in your browser.
Output will appear here.
JSON Lines workflow tips
Use JSON Lines Formatter when copied logs, exports, queue messages, or NDJSON samples contain one JSON record per line. Validate the line-oriented shape first, then convert to a JSON array only when another tool expects one combined JSON document.
Debug line errors quickly
If a record is malformed, the formatter reports the failing line number so you can fix a single log entry without scanning the whole pasted sample.
Move into JSON tools
Convert records to a JSON array before opening JSON Formatter, JSON Validator, or JSON Diff Checker for broader structured-data review.
Keep NDJSON compact
Use compact lines when downstream tools expect one JSON object per line, such as log fixtures, import notes, streaming examples, or queue payload samples.
What this tool does
This JSON Lines formatter checks each non-empty line as its own JSON record, reports the exact line with invalid JSON, and can return pretty records, compact NDJSON, or a standard JSON array for debugging, fixtures, logs, and API examples.
Common use cases
Format, validate, normalize, or convert pasted JSON Lines and NDJSON records for logs, fixtures, API examples, and data handoffs.
Use JSON Lines Formatter when you are working with copied API payloads, logs, encoded values, config snippets, identifiers, or debugging data and need a quick browser-local check before pasting the result into docs, tickets, tests, or another developer tool.
How to use it
- Paste JSON Lines or NDJSON where each non-empty line is one valid JSON value or object.
- Choose pretty lines, compact lines, or JSON array output depending on the next workflow step.
- Copy the normalized output into JSON Formatter, JSON Validator, JSON Diff Checker, or API documentation when needed.
Example workflow
Copy a small payload or encoded value from an API response, request URL, log line, or config file. Run the focused check here, confirm the output is readable, then continue with related developer data tools such as validation, formatting, decoding, timestamp conversion, or CSV/JSON conversion.
Privacy note
Client-side only: JSON Lines formatting runs in your browser and pasted records are not uploaded, stored, fetched, or logged.
FAQ
What is JSON Lines or NDJSON?
JSON Lines, also called NDJSON, stores one complete JSON value per line. It is common in logs, streaming exports, queue messages, fixtures, and data handoffs.
Does this upload my JSON Lines records?
No. Formatting runs locally in your browser and ClearUtils does not upload, store, fetch, or log pasted records.
Can it show which line is invalid?
Yes. If a record cannot be parsed as JSON, the tool reports the line number with the JSON parse error so you can fix the specific record.
Can I convert JSON Lines to a JSON array?
Yes. Choose JSON array mode to wrap parsed records in one formatted array for JSON Formatter, validators, docs, or examples.
When should I keep compact lines?
Use compact lines when another workflow expects one JSON object per line, such as log samples, NDJSON imports, or streaming payload examples.
Explore more tools
Browse the Developer Tools hub or continue with the Developer Data Toolkit when this task is part of a larger workflow.