For Prompt Engineers

Test Prompt Variables
Across Every Combination

Define prompts with {{variables}}, set value ranges, and instantly compare AI outputs side-by-side. Stop guessing — start testing.

Get Access — $29/mo
Prompt template

Write a {{tone}} email to {{name}} about {{topic}}.

{{tone}}
formal, casual, bold
{{name}}
Alex, Jordan
{{topic}}
pricing, onboarding
→ 12 combinations generated & compared automatically

Simple Pricing

Pro
$29
/month
  • ✓Unlimited prompt templates
  • ✓Up to 50 variables per prompt
  • ✓Auto-generate all combinations
  • ✓Side-by-side output comparison
  • ✓Export results as CSV or JSON
  • ✓Priority support
Start Testing Now

FAQ

What AI models are supported?
You can connect any OpenAI-compatible API. Works with GPT-4, Claude, Mistral, and more — just bring your own API key.
How many combinations can I test at once?
Up to 500 combinations per test run. Variables multiply across each other, so 3 variables with 5 values each = 125 combinations instantly.
Can I save and reuse test suites?
Yes. All your prompt templates and variable sets are saved to your dashboard so you can re-run, tweak, and compare across versions.