Promptfoo vs OpenAI Responses API
A side-by-side comparison to help you choose the right tool.
88
Promptfoo scores higher overall (88/100)
But the best choice depends on your specific needs. Compare below.
| Feature | Promptfoo | OpenAI Responses API |
|---|---|---|
| Our score | 88 | 87 |
| Pricing | Open-source core; free to run in your own workflows. | Usage-based API pricing; costs depend on the models and tools you use. |
| Free plan | Yes | No |
| Best for | Teams serious about AI testing discipline, Developers comparing prompts and providers, Organizations building evals into release workflows | Product teams building assistants or agents on OpenAI, Developers migrating from older endpoint patterns, Apps that need streaming and tool invocation in one API |
| Platforms | mac, windows, linux, api | api |
| API | Yes | Yes |
| Languages | en | en |
| Pros |
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| Cons |
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| Visit site | Visit site |
- Pricing
- Open-source core; free to run in your own workflows.
- Free plan
- Yes
- Best for
- Teams serious about AI testing discipline, Developers comparing prompts and providers, Organizations building evals into release workflows
- Platforms
- mac, windows, linux, api
- API
- Yes
- Languages
- en
- Pricing
- Usage-based API pricing; costs depend on the models and tools you use.
- Free plan
- No
- Best for
- Product teams building assistants or agents on OpenAI, Developers migrating from older endpoint patterns, Apps that need streaming and tool invocation in one API
- Platforms
- api
- API
- Yes
- Languages
- en
88Choose Promptfoo if:
- You are Teams serious about AI testing discipline
- You are Developers comparing prompts and providers
- You are Organizations building evals into release workflows
- You want to start free
87Choose OpenAI Responses API if:
- You are Product teams building assistants or agents on OpenAI
- You are Developers migrating from older endpoint patterns
- You are Apps that need streaming and tool invocation in one API
FAQ
- What is the difference between Promptfoo and OpenAI Responses API?
- Promptfoo is an open-source testing and evaluation framework for prompts and models, designed to fit into ci/cd and comparison workflows. OpenAI Responses API is openai's newer response-oriented api surface for building assistants and agents with streaming, tools, and model control.
- Which is cheaper, Promptfoo or OpenAI Responses API?
- Promptfoo: Open-source core; free to run in your own workflows.. OpenAI Responses API: Usage-based API pricing; costs depend on the models and tools you use.. Promptfoo has a free plan.
- Who is Promptfoo best for?
- Promptfoo is best for Teams serious about AI testing discipline, Developers comparing prompts and providers, Organizations building evals into release workflows.
- Who is OpenAI Responses API best for?
- OpenAI Responses API is best for Product teams building assistants or agents on OpenAI, Developers migrating from older endpoint patterns, Apps that need streaming and tool invocation in one API.