45 chars · 2 lines
84 chars · 10 lines
JSON Lines guide
Paste JSON Lines, NDJSON, newline-delimited JSON, or a regular JSON array into the tool above. Validate one-record-per-line data, preview JSONL as an array, normalize compact records, or convert an array into JSONL without uploading it. This tool is free to use. No account or payment is required.
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A regular JSON document has one root value, often an object or array. JSONL stores one complete JSON value on each line without wrapping all records in a top-level array.
This format is common for logs, data exports, streaming pipelines, and machine-learning datasets because records can be processed independently.
The validator parses every non-empty line separately and reports the line that contains invalid JSON. A broken record does not hide where the error occurred in the rest of the file.
Array preview wraps parsed records in a readable JSON array for inspection. Normalize mode writes one compact JSON value per line, while Array → JSONL accepts a top-level JSON array and writes each array item as its own compact JSONL record.
Two independent JSON records remain on separate lines after normalization.
{"id":1,"name":"Ada"}
{"id":2,"name":"Linus"}{"id":1,"name":"Ada"}
{"id":2,"name":"Linus"}Common questions
They are commonly used as names for the same one-JSON-value-per-line format.
No. Each record must be complete on one line. Pretty-printed multi-line objects should be converted to compact JSON first.
Each line may contain any valid JSON value, although datasets most commonly use one object per line.
No. Imported files and pasted records are processed locally in your browser.
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