John Damask

JSON Eval Maker

A simple tool to create evaluation datasets in JSONL format.

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JSONL Eval Maker

A simple, browser-based tool for creating evaluation datasets in JSONL format. Perfect for machine learning practitioners who need to quickly label data for model evaluation, fine-tuning, or classification tasks.

What It Does

JSONL Eval Maker helps you transform raw text data into labeled evaluation datasets. You can:

Why It’s Useful

Creating evaluation datasets is a common but tedious task in machine learning. This tool eliminates the friction by providing:

How to Use

  1. Open jsonl-eval-maker.html in your browser
  2. Load your data by:
    • Pasting text (one record per line)
    • Uploading a text file
    • Uploading a CSV/TSV file (choose which column to label)
  3. Create labels using the input box and “Add” button
  4. Select an active label from the dropdown
  5. Click rows to instantly apply the label
  6. Customize your dataset:
    • Add extra columns using the “+” button
    • Right-click any cell to edit its content
    • Drag column borders to resize for better visibility
    • Delete unwanted rows using the × button
  7. Export your labeled dataset as JSONL

Features

Data Management

Editing & Labeling

Export & Compatibility

Technical Details

Built as a single HTML file with vanilla JavaScript - no dependencies or build process required. The app runs entirely client-side, so your data never leaves your browser.

Export formats:

Standard format:

{"input": "your text data", "ideal": "your_label"}
{"input": "more text data", "ideal": "another_label"}

With additional columns:

{"input": "your text data", "ideal": "your_label", "comment": "reasoning", "confidence": "high"}
{"input": "more text data", "ideal": "another_label", "comment": "uncertain", "confidence": "medium"}

OpenAI Item Schema format (for fine-tuning):

{"item": {"input": "your text data", "ideal": "your_label", "comment": "reasoning"}}
{"item": {"input": "more text data", "ideal": "another_label", "comment": "uncertain"}}

Use Cases

Getting Started

Simply download the jsonl-eval-maker.html file and open it in any modern web browser. No installation, no server setup, no dependencies - just start labeling your data!