Which variable styles work?

{{name}}, {{name|default}}, {name} and ${name}. The style is detected from the template, and you can pick one by hand if your text uses braces for other things.

Can I make a batch file for an API?

Yes. Fill the template from a CSV and download JSONL, one filled prompt per line, ready for a batch job.

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 / Prompt Template Filler

Prompt Template Filler

Turn {{variables}} in a prompt into a form, fill it live, or fill it from a CSV to make many prompts or a batch JSONL file.

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

How Prompt Template Filler works

Everything runs in your browser. Prompts, datasets and model files are never uploaded. Variables written as {{name}}, {{name|default}}, {name} or ${name} are found in order of first use. Each becomes a field. In CSV mode every row fills the template once, using the columns whose names match the variables.

Input: Text, CSV. Output: Text, JSONL.

How to use Prompt Template Filler

Paste your prompt template.
Fill the fields, or switch to Fill from a CSV and drop a file.
Check the filled prompt and its token estimate.
Copy it, or download prompts as JSONL or text.

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.

Prompt Template Filler FAQ

Which variable styles work?: {{name}}, {{name|default}}, {name} and ${name}. The style is detected from the template, and you can pick one by hand if your text uses braces for other things.
Can I make a batch file for an API?: Yes. Fill the template from a CSV and download JSONL, one filled prompt per line, ready for a batch job.
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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