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JSONL Validator
Processed Locally
Validate JSONL (JSON Lines) format and check each line for valid JSON syntax.
Frequently Asked Questions
The validator checks if each non-empty line in your input is valid JSON. It reports the total number of lines, how many are valid, how many are invalid, and provides detailed error messages for each problematic line.
No, empty lines are automatically skipped during validation. They do not count toward the total line count or affect validation results. This allows for more flexible JSONL formatting with blank lines for readability.
For each invalid line, the validator shows: the line number where the error occurred, the specific error message from the JSON parser, and a preview of the line content (first 100 characters if the line is long).
The validator supports files up to 2MB in size. For larger log files, consider splitting them into smaller chunks or using the first part of the file for validation. All processing happens locally in your browser for privacy.