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JSON Lines to JSON

Parses each nonblank line separately and collects the records into one JSON array.

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How JSON Lines to JSON works

Parses each nonblank line separately and collects the records into one JSON array. Errors identify the original line number.

Try an example

{"id":1} followed by a newline and {"id":2} becomes [{"id":1},{"id":2}].

Good to know

Processed in this browser. Maximum 100,000 input characters and 10,000 records. JavaScript JSON parsing can round large numbers and keeps the last duplicate key; quote identifiers to preserve them. Blank lines are ignored. Pretty-printed multiline records are not JSON Lines.

Your privacy

Processing happens on this device for this tool. We do not upload your input, put it in share links or save it to your favourites. Closing this tab discards the working input; downloaded results remain wherever you save them.

When this tool is useful

Use JSON Lines to JSON when you need a quick, local result and want the rule or limitation visible alongside it.

How to use it

  1. Enter the input using the labels shown.
  2. Run the operation and review the result.
  3. Download or copy the result only after checking it.

Checks before you rely on the result

  • Processed in this browser. Maximum 100,000 input characters and 10,000 records. JavaScript JSON parsing can round large numbers and keeps the last duplicate key; quote identifiers to preserve them. Blank lines are ignored. Pretty-printed multiline records are not JSON Lines.
  • Keep the original input when the operation creates a new copy.
  • Use the related tools below when the next step needs a different format.

This page is maintained with the tool implementation and its deterministic tests. If the result looks wrong, report the issue with a non-sensitive example.

Read the JSON Lines to JSON instructions

A useful next step

JSON to CSV
JSON Flattener
JSON to JSON Lines
Made for clarity. Built to be useful.Report an issue