PromptTester
August 13, 2025 ยท View on GitHub

Test and compare LLM prompts across OpenAI, Claude, and Gemini with real-time cost tracking.
Features
- Multi-Provider: OpenAI (GPT-4/5), Claude (Opus/Sonnet), Gemini (Pro/Flash)
- Batch Testing: Run multiple scenarios simultaneously
- Cost Tracking: Real-time pricing with token usage
- Comparison Mode: Side-by-side response comparison
- Import/Export: Share scenarios as JSON
Quick Start
# Install dependencies
npm install
# Copy and configure environment variables
cp .env.example .env
# Edit .env and add your API keys
# Start the app
npm start
- Configure API keys in
.envfile - Create test scenarios or use the existing ones in here.
- Run and compare results
Configuration
API keys are loaded from environment variables for security. Create a .env file based on .env.example:
REACT_APP_OPENAI_API_KEY=your-openai-key
REACT_APP_CLAUDE_API_KEY=your-claude-key
REACT_APP_GEMINI_API_KEY=your-gemini-key
How It Works
The app uses official SDKs to connect directly to each provider. It also calculates costs based on each provider's pricing structure.
License
MIT