Comparison

LM Evaluation Harness vs OpenAI Evals

On the evidence we track, LM Evaluation Harness leads this comparison with a composite score of 54/100. Scores are only directly comparable because these tools share a category; the full breakdown and every source is below.

Machine formatsJSONMarkdownGraphQLor send Accept: application/json
LM Evaluation Harness54
OpenAI Evals45
Score
Vioscale score
LM Evaluation Harness54 / 100low · 40%
OpenAI Evals45 / 100low · 30%
Pricing
Free tier
LM Evaluation Harness
OpenAI Evals
Model
LM Evaluation Harnesscommercial
OpenAI Evalscommercial
Price level
LM Evaluation Harnessfree
OpenAI Evalsfree
Transparent
LM Evaluation Harness
OpenAI Evals
Integrations
Count
LM Evaluation Harness5
OpenAI Evals3
Adoption
Dependent repos
LM Evaluation Harness252
OpenAI Evals1
Github stars
LM Evaluation Harness13,802
OpenAI Evals19,257
Activity
Commits last 30d
LM Evaluation Harness50
OpenAI Evals0
Release
Cadence days
LM Evaluation Harness66
OpenAI Evals
History
LM Evaluation Harness18 items
OpenAI Evals
License
Spdx
LM Evaluation HarnessMIT
OpenAI Evals
Language
Primary
LM Evaluation HarnessPython
OpenAI EvalsPython

Capabilities

Feature-by-feature on the axes that matter for ai evals testing. “-” means undocumented, not absent.

Capabilities
Architecture model
LM Evaluation HarnessOpen source CLI
OpenAI EvalsOpen source CLI
LLM as a judge prompt grading framework
LM Evaluation Harness-
OpenAI Evals
Specialized rag metrics faithfulness context relevance
LM Evaluation Harness-
OpenAI Evals-
Deterministic regex and json schema assertions
LM Evaluation Harness-
OpenAI Evals
Synthetic test dataset generation from documents
LM Evaluation Harness-
OpenAI Evals
Ci cd github actions pipeline blocking gates
LM Evaluation Harness-
OpenAI Evals
Red teaming and adversarial vulnerability scanning
LM Evaluation Harness-
OpenAI Evals-
Multi model side by side ab regression testing
LM Evaluation Harness
OpenAI Evals-
Human in the loop hitl annotation UI
LM Evaluation Harness-
OpenAI Evals-
Dashboard analytics for metric drift over time
LM Evaluation Harness-
OpenAI Evals-
SOC2 type ii
LM Evaluation Harness-
OpenAI Evals-
Mit or apache permissive oss license
LM Evaluation Harness-
OpenAI Evals
Pricing model
LM Evaluation HarnessFree open source
OpenAI EvalsFree open source

What each one is

The product in its own terms, so the numbers below have context.

LM Evaluation Harness

Leader

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.

Independently observed

OpenAI Evals

A framework that lets developers create and run evaluations to measure LLM performance, providing both pre-built benchmarks and tools to write custom tests tailored to specific use cases without requiring proprietary evaluation infrastructure.

Independently observed

Pricing

List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.

LM Evaluation Harness

Leader
Open sourceFree tier

Free and open source

as of verify ↗

OpenAI Evals

FreeFree tier

Free and open-source

as of verify ↗

Platform & deployment

Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.

Platforms
Web
LM Evaluation Harness
OpenAI Evals
CLI
LM Evaluation Harness
OpenAI Evals
Deployment
Cloud / SaaS
LM Evaluation Harness
OpenAI Evals
Self-hosted
LM Evaluation Harness
OpenAI Evals

Integrations

What each product connects to. Counts come from the vendor's own integration directory where one exists.

In common (1)
  • GitHub

LM Evaluation Harness

Leader
5 total - 4 not shared
  • Hugging Face
  • PyTorch
  • VLLM
  • OpenAI-compliant APIs
Independently observed

OpenAI Evals

3 total - 2 not shared
  • OpenAI API
  • Snowflake
Independently observed

Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.