HarmBench vs Promptfoo
HarmBench
github.com
Promptfoo
promptfoo.devSide by side
| Figure | HarmBench | Promptfoo |
|---|---|---|
| Price from | — | Free |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | Yes |
| Web | — | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 0 | 3 |
| Spec score · LLM Evaluation Tools | 7.2 (#21) | 8.4 (#6) |
| Spec score · AI Security Testing Tools | 7.1 (#22) | 8.5 (#6) |
| Installation | The README instructs users to clone the repository, install requirements with pip, and download the en_core_web_sm spaCy model. | Installation is available through npm, npx, Homebrew, and a project dependency; npm and npx require Node.js 22.22.0 or newer. |
| License | The public GitHub repository lists an MIT license. | The open-source project is distributed under the MIT license. |
| Support | The repository documentation invites users to submit a pull request for support for another cluster manager. | Community support is provided through chat and GitHub issues, while Enterprise includes professional services and dedicated Slack support. |
Plans
In their own words
Promptfoo
Promptfoo helps developers and enterprises evaluate prompts and test AI applications for security risks. It compares prompt outputs across multiple models in a web view. Red-team testing simulates users to look for prompt injections, jailbreaks, data leaks, business rule violations and insecure agent tool use. Its getting-started guide lists more than 60 providers, including OpenAI, Anthropic, Google and local models such as Ollama. Integrations include CI systems such as GitHub Actions, GitLab CI, Jenkins, Azure Pipelines, CircleCI and Bitbucket Pipelines, plus Splunk, Burp Suite, Google Sheets and MCP. Installation is available through npm, npx or Homebrew. Promptfoo requires Node.js 22.22.0 or newer and recommends Node.js 24 LTS. The free Community plan includes all LLM evaluation features and 10k red-team probes per month, and can run locally or be self-hosted. Enterprise includes managed cloud deployment; On-Premise runs on customer infrastructure. Promptfoo says it is based in San Francisco, is now part of OpenAI and remains open source.