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JSON Lines Validator

Validate JSON Lines (NDJSON) documents and identify invalid records.

What is JSON Lines Validator?

The JSON Lines Validator checks every line of an NDJSON file individually, helping you detect malformed records while ensuring the overall file is valid.

How to use

  1. Paste or upload a JSON Lines file.
  2. Run validation.
  3. Review any reported errors.

Features

  • Validate each JSON record
  • Highlight syntax errors
  • Fast processing
  • Large file support

Common Use Cases

  • Checking log files
  • Validating exported datasets
  • Preparing data imports
  • Debugging NDJSON

Example

Input
{"id":1}
{"id":2}
Output
✓ All lines are valid

FAQ

Does it validate every line separately?

Yes. Each line is treated as an independent JSON object.

Can it detect invalid records?

Yes. Errors are reported for individual lines.

Does it support large files?

Yes. Performance depends mainly on your browser.