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Promptfoo (open source)

Open-source CLI for LLM evals and red teaming

Automated platformAgents and toolsCompliance mappingOpen source

Promptfoo is a CLI and library for evaluating and red teaming LLM apps, agents and RAG pipelines, with declarative configs that run in CI/CD. It has about 27,000 GitHub stars and released 0.125.1 on Oct 25, 2026. Its red team configs include presets for OWASP LLM and Agentic Top 10, MITRE ATLAS, NIST AI RMF, the EU AI Act and ISO/IEC 42001.

Best for: Developers who want red teaming as part of their test suite.

Open source (MIT), now part of OpenAI (deal announced Mar 2026)

  • ✓ Maps to OWASP
  • ✓ Maps to MITRE ATLAS
  • ✓ Maps to the EU AI Act
  • – SOC 2 or ISO 27001
Visit Promptfoo (open source)

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

1 Legal namePromptfoo
2 HeadquartersNot disclosed
3 Founded2023
4 TeamNot disclosed
5 What they testLLM apps, Agents and tool use, RAG, Prompt injection and jailbreaks, Data leakage, Bias and harms
6 FrameworksOWASP LLM Top 10, OWASP Agentic Top 10, MITRE ATLAS, NIST AI RMF, EU AI Act, ISO/IEC 42001, OWASP API Top 10, GDPR, DoD AI Ethics Principles
7 CertificationsNot disclosed
8 Published pricesFree (MIT). Hosted Community tier free up to 10k red teaming probes a month; Enterprise and On-Premise custom.
9 Customers and partnersNot disclosed

Where we recommend them

Worth knowing before you sign

  • Now owned by OpenAI; Promptfoo says it stays MIT licensed, but watch neutrality if you test other providers’ models.
  • Deal close date and terms not published.

Go to Promptfoo (open source)'s site

Sources

  1. GitHub: promptfoo/promptfoo
  2. GitHub: releases
  3. Promptfoo blog: joining OpenAI
  4. Promptfoo docs: red team configuration

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

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