LM Evaluation Harness vs Promptfoo
No leader: the top candidate Promptfoo has only 0.22 confidence (low), below the 0.35 needed to declare a winner. 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 framework for conducting few-shot evaluation of language models against various tasks and benchmarks. Supports multiple model backends, custom evaluation metrics, and extensible task definitions for assessing model capabilities and performance.
Promptfoo
Automated testing and security evaluation framework for AI applications, with support for comparing multiple model providers and identifying potential vulnerabilities through red teaming and assertion-based validation.
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
- Azure
- Bedrock
- Ollama
- Gemini
LM Evaluation Harness or Promptfoo: which one depends on you
A composite score cannot know your constraints. Describe them and both get re-weighted against what you actually need, with the evidence behind every position.
Free to run, no account needed to start. How the evaluation works
Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.