Compare system prompts side-by-side across any LLM provider. Run experiments, visualize differences, and ship prompts with confidence.
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A purpose-built toolkit for prompt engineers who demand precision and reliability.
Compare two prompts simultaneously across your entire dataset. See differences at a glance and make data-driven decisions.
OpenAI, Anthropic, Google Gemini — use your own API keys. Add new providers with a single config file.
Import JSON datasets or create them in-app. Add expected outputs for regression testing and quality assurance.
Track wins, losses, and ties across experiments. Identify which prompt performs best for different input types.
Your API keys are encrypted at rest and never logged. Your data stays private and under your control.
Watch experiments run live with streaming results. See outputs as each example completes processing.
No complex configuration. No steep learning curve. Just results.
Sign up and add your API keys for OpenAI, Anthropic, or Google. Keys are encrypted and never shared.
Organize your work into projects. Each project contains its own prompts, datasets, and experiments.
Write versioned prompts with system messages and user templates. Use {{input}} placeholders for dynamic content.
Build test examples directly in the app or import from JSON. Add expected outputs for regression testing.
Compare multiple prompts across different models. Watch results stream in real-time and analyze performance.
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