Promptfoo vs Patronus AI

Both compete in Red-Teaming & AI Security. Promptfoo positions itself as “Open-source tool for evaluating and red-teaming LLM apps, agents, and RAG systems”, while Patronus AIleads with “Automated evaluation, guardrails, and judges for LLM and agent reliability”. The table below compares what each publishes.

Where Promptfoo pulls ahead

Developer teams wanting free, open-source, CI/CD-integrated evaluation and red teaming of LLM apps

Where Patronus AI pulls ahead

Publishes support for NIST AI RMF, which Promptfoo does not. ML and product teams that need automated, research-grade evaluation plus guardrails to ship reliable LLM apps

	Promptfoo	Patronus AI
Positioning	Open-source tool for evaluating and red-teaming LLM apps, agents, and RAG systems	Automated evaluation, guardrails, and judges for LLM and agent reliability
Category	Red-Teaming & AI Security	Red-Teaming & AI Security
Frameworks	None published	NIST AI RMF
Deployment	Open-source, SaaS, API	SaaS, API
Built for	Data Science / ML, Security	Data Science / ML, Risk, Compliance
Founded	2023	2023
Headquarters	USA	San Francisco, California, USA
Ownership	Acquired by OpenAI (2026); previously VC-backed	Independent, venture-backed
Funding	~$23.4M raised prior to acquisition; $5M seed (a16z, 2024) and $18.4M Series A led by Insight Partners (2025)	$17M Series A (2024) led by Notable Capital, with Lightspeed and Datadog (~$20M total); subsequent Series B reported
Pricing	Open-source (MIT license), free; paid enterprise platform	Commercial SaaS / usage-based; some open evaluators and models available
Key capabilities	LLM evaluation and benchmarking Automated red teaming and vulnerability scanning Declarative test configs Prompt and model comparison CI/CD integration Local/self-hosted execution	Automated LLM evaluation and benchmarking Adversarial test-case generation Lynx hallucination detection and judge models Percival agent debugging Runtime guardrails PII, safety and compliance checks
Integrations	OpenAI, Anthropic, Google Gemini, DeepSeek, CI/CD pipelines, GitHub	OpenAI, Anthropic, Bifrost gateway, Common ML/LLM stacks via API
Notable customers	OpenAI, Anthropic, Fortune 500 enterprises	None published
Best for	Developer teams wanting free, open-source, CI/CD-integrated evaluation and red teaming of LLM apps	ML and product teams that need automated, research-grade evaluation plus guardrails to ship reliable LLM apps
Limitations	Developer-oriented and requires engineering effort to configure; broader governance/compliance features live in the paid enterprise tier.	More an evaluation/observability platform than a hardened security firewall; deepest value requires building evaluation into workflows; younger company still expanding enterprise features

Which should you shortlist?

Choose Promptfoo if developer teams wanting free, open-source, CI/CD-integrated evaluation and red teaming of LLM apps

Choose Patronus AI if mL and product teams that need automated, research-grade evaluation plus guardrails to ship reliable LLM apps

Neither is a substitute for a governance program. Whichever you pick, you still need people who can define the policies the tool enforces.

Full Promptfoo profile →Full Patronus AI profile →

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