Are tool calls and system prompts kept?

System messages are kept, and you can add one to every row. Tool turns are kept in formats that support them (OpenAI chat and ShareGPT) and left out of formats that have no place for them, such as Alpaca.

Can I convert a spreadsheet of questions and answers?

Yes. Save it as CSV, drop it here and pick which column is the question and which is the answer.

Are my files uploaded?

No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.

Is it free? Are there limits or watermarks?

Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.

Does it work offline?

Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.

Home / AI Builder / Dataset Format Converter

Dataset Format Converter

Convert fine-tuning data between OpenAI chat JSONL, ShareGPT, Alpaca, prompt and completion, and CSV, with an optional system prompt.

Free, no uploads, no sign-up. Runs 100% in your browser.

How Dataset Format Converter works

Everything runs in your browser. Prompts, datasets and model files are never uploaded. Each row is read into a common conversation (system, user, assistant and tool turns), then written in the format you pick. CSV columns for the question, answer, extra input and system message are matched by name and can be changed.

Input: JSONL, JSON, CSV. Output: JSONL, CSV.

How to use Dataset Format Converter

Paste JSONL or drop a JSONL or CSV file.
For CSV, check which column is the question and which is the answer.
Pick the output format and add a system prompt if you want one.
Download the converted file.

Tips

Prompts, datasets and API keys never leave your device, so these tools are safe for private work.
Tokenizers and AI models download once and are cached by your browser.

Dataset Format Converter FAQ

Are tool calls and system prompts kept?: System messages are kept, and you can add one to every row. Tool turns are kept in formats that support them (OpenAI chat and ShareGPT) and left out of formats that have no place for them, such as Alpaca.
Can I convert a spreadsheet of questions and answers?: Yes. Save it as CSV, drop it here and pick which column is the question and which is the answer.
Are my files uploaded?: No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
Is it free? Are there limits or watermarks?: Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
Does it work offline?: Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.

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