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HarmBench

Benchmark for automated red teaming and refusal

Frontier model safetyOpen source

HarmBench is a standardized evaluation framework for automated red teaming and for how reliably models refuse harmful requests, from the Center for AI Safety and academic collaborators. It is widely used to compare automated jailbreak methods.

Best for: Watch only: research comparisons of jailbreak methods.

Open source (MIT), maintained by the Center for AI Safety

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

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

1 Legal nameHarmBench
2 HeadquartersNot disclosed
3 Founded2024
4 TeamNot disclosed
5 What they testFoundation models, Prompt injection and jailbreaks, Bias and harms, Frontier safety (CBRN, cyber), Multimodal
6 FrameworksNot disclosed
7 CertificationsNot disclosed
8 Published pricesFree (MIT)
9 Customers and partnersNot disclosed

Worth knowing before you sign

  • No commits since Aug 2024 and no tagged releases.

Go to HarmBench's site

Sources

  1. GitHub: centerforaisafety/HarmBench
  2. arXiv: HarmBench paper

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

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