JSONL / NDJSON Converter
Validate newline-delimited JSON with source-line errors, convert JSONL to a JSON array, or export an array as compact NDJSON without rounding large integers.
Paste input or try the example.
Supports one complete JSON value per line, including primitives. Up to 1,000 lines/records, 250,000 characters and 20,000 total values. Numeric literal spellings are preserved.
Open a UTF-8 text file
Using JSONL / NDJSON Converter
Validate newline-delimited JSON with source-line errors, convert JSONL to a JSON array, or export an array as compact NDJSON without rounding large integers.
- Paste your input, open a UTF-8 file or load the example.
- Choose the operation and settings, then click Convert records.
- Read the status and limitations, then copy or download the output.
Example
{"id":1,"text":"Hello"}
{"id":9007199254740993,"text":"World"}
Supports one complete JSON value per line, including primitives. Up to 1,000 lines/records, 250,000 characters and 20,000 total values. Numeric literal spellings are preserved.Questions & answers
What are JSONL and NDJSON?
Both commonly describe one JSON value per line. Newlines inside strings must be escaped as \n rather than appearing literally inside a record. This tool accepts LF and CRLF line endings.
How are invalid records handled?
Conversion stops with the source line number and parse error. No invalid records are silently discarded. Empty lines can either be ignored or rejected explicitly.
Can I convert back to JSONL?
Choose JSON array to JSONL and supply a top-level array. Each element becomes one compact line, ending with a newline. The blank-line option only affects JSONL input.
Does it preserve numbers and key order?
Yes. The existing syntax-aware JSON parser retains numeric spelling and object member order. Duplicate keys are rejected. Output allows up to 1,500,000 characters.
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