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Promptfoo

Automated red teaming and evals platform, now owned by OpenAI

Automated platformAgents and toolsCompliance mapping

Promptfoo sells enterprise and on-premise versions of its red teaming and evals tool, adding application-specific attacks, continuous monitoring, remediation tracking and compliance dashboards, plus an MCP Proxy. It ships presets for OWASP LLM, Agentic and API Top 10, MITRE ATLAS, NIST AI RMF, ISO/IEC 42001 and the EU AI Act. OpenAI agreed to buy it in Mar 2026 and committed to keep the open-source project and serve current customers.

Best for: Engineering teams that want red teaming in CI, from a free tier to enterprise.

Acquired by OpenAI (announced Mar 2026); GitHub says it is now part of OpenAI, close date not published

  • ✓ Maps to OWASP
  • ✓ Maps to MITRE ATLAS
  • ✓ Maps to the EU AI Act
  • ✓ SOC 2 or ISO 27001
Visit Promptfoo

Facts checked November 9, 2026 against the sources listed below. Promptfoo does not pay to appear here.

1 Legal namePromptfoo, Inc.
2 HeadquartersSan Francisco Bay Area, USA
3 Founded2024
4 TeamNot disclosed
5 What they testLLM apps, Agents and tool use, RAG, Prompt injection and jailbreaks, Data leakage, Bias and harms, Model supply chain
6 FrameworksOWASP LLM Top 10, OWASP Agentic Top 10, MITRE ATLAS, NIST AI RMF, EU AI Act, ISO/IEC 42001, OWASP API Security Top 10, DoD AI Ethical Principles, GDPR
7 CertificationsSOC 2, ISO 27001 (badges on site)
8 Published pricesCommunity: free, with red teaming up to 10k probes a month. Enterprise and On-Premise: custom.
9 Customers and partnersSays more than 25% of the Fortune 500 use it, with customers unnamed (a top-5 retailer, a top-3 US carrier, a top foundation model lab).

Where we recommend them

Worth knowing before you sign

  • Owned by a model vendor: if you test models from OpenAI’s competitors, watch neutrality and the roadmap.
  • No public closing date for the OpenAI deal.
  • Company blog shows no posts after Mar 12, 2026; pricing page has no acquisition notice.

Go to Promptfoo's site

Sources

  1. Vendor blog: Promptfoo is joining OpenAI
  2. TechCrunch: OpenAI acquires Promptfoo
  3. Vendor: pricing
  4. Vendor docs: OWASP LLM Top 10 preset
  5. Insight Partners: Series A

Work at Promptfoo? Send corrections with a source to editors@bestairedteamingcompanies.com. We fix verified errors within five business days.

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