CONVERT JSON LINES LOCALLY
Turn line-delimited records into a usable file.
Convert JSON Lines into a JSON array or CSV in your browser. Blank lines are ignored, malformed records are reported by line, and input stays on your device.
One JSON value per non-empty line · processed locally
Paste JSON Lines input or try the example.
Conversion rules
Each non-empty line is parsed as its own JSON value. Blank or whitespace-only lines are ignored. Invalid lines are reported by line number and skipped. JSON array output accepts every valid JSON value. CSV output includes only object records: columns follow the first appearance of each key, missing values are empty, nested values become compact JSON text, and arrays or scalar values are reported and skipped.
Method: parse records independently with the browser's JSON parser, retain source line numbers for errors, then serialize valid values as an array or quote CSV cells when they contain commas, quotes, or line breaks.
Page content updated November 3, 2026.
Runs in your browser. No uploads. No account.
Good to know
Are blank lines errors?
No. Empty and whitespace-only lines are ignored. Every non-empty line must contain one complete JSON value; malformed lines are listed and excluded from output.
Can JSONL contain values other than objects?
Yes. JSON array output keeps valid objects, arrays, strings, numbers, booleans, and null values. CSV is tabular, so it includes object records only and reports other value types as skipped.
How are CSV columns chosen?
Column names are the unique object keys in order of first appearance. Missing keys produce empty cells. Arrays and objects inside cells are written as compact JSON text.
Does my data leave this browser?
No. Parsing and conversion happen in this browser tab. The tool does not upload or store your input.
Is it free?
Yes, during beta. Optional usage-credit plans are coming soon. Payments are not available and no credits are required.
Source
The format rules and blank-line behavior follow JSON Lines documentation, checked November 3, 2026.
How it works
1. Paste one JSON value per line. 2. Choose JSON array or CSV output. 3. Convert, review any skipped line numbers, then copy or download the result.
Good to know
What happens to blank lines and invalid records?
Empty lines are ignored. Malformed non-empty lines are reported by line number and skipped; valid lines are still converted.
Which JSONL values can be converted to CSV?
CSV output includes JSON objects only. Other valid JSON values are reported and skipped; JSON array output preserves all valid JSON value types.
How are CSV columns selected?
Object keys become columns in first-seen order. Missing values are empty, and nested values are represented as compact JSON text.
Does the tool upload my input?
No. Parsing and conversion happen locally in this browser tab; the tool does not upload or store your input.
Is it free?
Yes, during beta. Optional usage-credit plans are coming soon. Payments are not available and no credits are required.