Chat & Fine-Tuning JSONL Dataset Validator

Validate provider-neutral chat-message or prompt/completion JSONL datasets for LLM fine-tuning before upload by detecting syntax, role, content, assistant-example problems, duplicates, and estimating tokens.

Runs locally in your browser
Dataset rows are parsed only in this browser. The validator does not upload training data or claim provider-specific acceptance.
JSONL dataset

Validate structure before uploading training data

This provider-neutral check covers JSONL syntax, roles, content, assistant examples, duplicates and approximate size. Always run the target provider’s current validation and policy checks before creating a job.

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