JSONL tools

Validate JSONL line by line, convert JSONL to a JSON array, or turn a JSON array into JSONL.

JSON Lines ↔ pretty JSON, plus a validator that lists every bad line.

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How to use

  1. Paste JSONL or a JSON array.
  2. Pick validate / JSONL→JSON / JSON→JSONL.
  3. Copy or download the result.

What it supports

Up to 100,000 lines / 2 MB of input. Validation reports every bad line with its parse error; conversion inherits the input size limit.

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