How are placeholders matched?

The first CSV row is treated as headers. Any double-brace token like {{column}} in your template is replaced with that row's value for the matching header. Unmatched tokens are left as-is so you can spot typos.

Where does my API key and data go?

The key and every request go directly from your browser to the provider and are never stored or sent to us. Your CSV is parsed and processed entirely in the page.

Won't this hit rate limits?

Requests are run with a small delay and limited concurrency to stay under typical rate limits. If a row errors, it is recorded in the output with the error text and the batch continues rather than stopping.

What does the output look like?

A CSV with all your original columns plus an added column containing the model's response for each row, ready to download and open in a spreadsheet.

How big a batch can I run?

It runs in your browser, so practical limits are your patience and your provider's rate limits and budget. For very large jobs, split the CSV — and remember every row is a billed API call.

Batch Prompt Runner (BYO Key)

Batch prompt runner

When you need to run the same prompt over a list — classify a hundred tickets, summarise fifty product descriptions, extract fields from a column of text — the batch prompt runner does it in one pass. Paste a CSV of inputs and a prompt template with placeholders matching your column headers; the tool fills the template per row, sends each to the model with your own API key, and hands you back a CSV with a new output column. It throttles requests to respect rate limits and records errors per row instead of failing the whole job.

How it works

You paste a CSV with a header row and a template using double-brace placeholders like {{name}} that map to those headers. For each data row, the tool substitutes the values, sends the filled prompt to your chosen model, and collects the response. Requests run with limited concurrency and a small delay so you stay under typical rate limits; any row that errors is captured with its error message and the batch keeps going. A live progress bar shows how far along it is. When finished, you download a CSV containing your original columns plus an added response column. Everything happens in your browser — the key and all requests go directly to the provider and are never stored.

Tips and notes

Match headers exactly. {{Name}} and {{name}} are different. Unmatched placeholders are left visible so typos are easy to spot.
Test one row first. Run a tiny CSV to confirm the template and output before launching a big, billable batch.
Mind the cost. Every row is a real API call billed to your account; a thousand rows is a thousand requests.
Split very large jobs. Browser tabs are not ideal for huge batches — chunk the CSV and run pieces.