LM Evaluation Harness vs Promptfoo
No clear leader: Promptfoo (54.4) and LM Evaluation Harness (53.7) are within the 5-point margin; treat as a tie. The attribute-by-attribute breakdown below, with a source and date on every value, is the honest way to compare them.
Capabilities
Feature-by-feature on the axes that matter for ai evals testing. “-” means undocumented, not absent.
What each one is
The product in its own terms, so the numbers below have context.
LM Evaluation Harness
A Python-based evaluation framework that enables testing of language models against 60+ standard academic benchmarks with support for various model formats, APIs, and custom evaluation metrics.
Promptfoo
A comprehensive LLM security testing solution that automatically scans for vulnerabilities such as prompt injections and jailbreaks through dynamic red teaming. Offers both open-source software for local testing and enterprise SaaS with team collaboration, continuous monitoring, and compliance dashboards.
Pricing
List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.
Promptfoo
Free open-source Community tier; Enterprise and On-Premise plans with custom pricing
- CommunityFree
- All LLM evaluation features
- All model providers and integrations
- Red teaming (10k probes/month)
- Custom integration with your own app
- Run locally or self-host on your own infrastructure
- +2 more
- EnterpriseContact sales
- All Community features
- Custom red teaming limits
- Team sharing & collaboration
- Continuous monitoring
- Centralized security/compliance dashboard
- +6 more
- On-PremiseContact sales
- Complete data isolation
- On-premise deployment
Platform & deployment
Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.
Integrations
What each product connects to. Counts come from the vendor's own integration directory where one exists.
- GitHub
LM Evaluation Harness
- Hugging Face
- PyTorch
- VLLM
- OpenAI-compliant APIs
Promptfoo
- OpenAI
- Anthropic
- Google (Gemini)
- DeepSeek
- MCP (Model Context Protocol)
- CI/CD pipelines
- Webhooks
- Agent frameworks
- CI/CD platforms
- Python providers
Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.