opencompass
OpenCompass is an open-source LLM evaluation platform supporting 100+ datasets and a wide range of models (Llama, Mistral, GPT-4, Claude, Qwen, etc.). It provides standardized benchmarking tools and leaderboards for assessing language model quality and effectiveness.
Key facts
Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.
| Field | Value |
|---|---|
| Repository | open-compass/opencompass |
| Owner | open-compass |
| Primary language | Python |
| License | Apache-2.0 — OSI-approved |
| Stars | 7.2k |
| Forks | 799 |
| Open issues | 436 |
| Latest release | 0.5.3 (2026-06-29) |
| Last updated | 2026-07-07 |
| Source | https://github.com/open-compass/opencompass |
What opencompass is
Python-based evaluation framework offering configurable test harnesses for multiple LLM backends (HuggingFace, vLLM, LMDeploy), dataset management via local/ModelScope sources, and composable evaluation pipelines including LLM-as-judge and math-specific evaluators. Recent additions include CascadeEvaluator for sequential evaluation chains and post-processing via XFinder.
Get the opencompass source
Clone the repository and explore it locally.
git clone https://github.com/open-compass/opencompass.gitcd opencompass# follow the project's README for install & configurationNeed it deployed, integrated, or customized instead? DEV.co ships production installs.
Best use cases
Implementation considerations
- Python 3.8+ environment; install via pip or source. Requires GPU(s) for practical LLM inference; CPU-only is very slow for benchmarks.
- Decide on backend: HuggingFace (default), vLLM (faster inference), or LMDeploy. Configure via command-line flags or deployment APIs.
- Define or import datasets; OpenCompass provides 100+ built-in configs. For custom datasets, extend Dataset class and register in YAML.
- Plan evaluation scope: dataset selection, model list, metric preferences. Large evaluations (many models × many datasets) take hours/days.
- For LLM-as-judge flows, ensure target judge model (e.g., GPT-4) is accessible and budgeted; costs scale with evaluation size.
When to avoid it — and what to weigh
- Real-time or low-latency inference systems — OpenCompass is a batch evaluation platform, not an inference server. For serving models in production, use vLLM, TensorRT, or similar independently.
- Minimal infrastructure or single-machine deployment — Evaluating 100+ datasets across multiple models requires significant compute. Distributed setups across GPUs/TPUs are expected; not suitable for lightweight deployments.
- Closed/proprietary model evaluation without API keys — Evaluation of OpenAI, Claude, or other closed models requires valid API credentials. If you cannot provide these, you cannot evaluate those models.
- Turnkey evaluation without configuration — OpenCompass requires familiarity with YAML configs, model definitions, and dataset specifications. It is not a no-code platform; setup and tuning are essential.
License & commercial use
Apache License 2.0 (Apache-2.0). Permissive OSI-approved license: allows commercial use, distribution, modification, and private use with attribution and license notice retention.
Apache-2.0 is permissive for commercial use. You may run OpenCompass to evaluate models for commercial products, publish rankings, and modify code. Ensure LICENSE file is retained in distributions. No warranty or liability limitations from licensor. Review terms for closed-model evaluation (e.g., OpenAI API ToS are separate).
DEV.co evaluation signals
Editorial assessment — not user reviews. Directional, with an explicit confidence level.
| Signal | Assessment |
|---|---|
| Maintenance | Active |
| Documentation | Strong |
| License clarity | Clear |
| Deployment complexity | Moderate |
| DEV.co fit | Good |
| Assessment confidence | High |
Runs model inference locally or via third-party APIs (OpenAI, Claude, etc.). Ensure API keys are stored securely (environment variables, not in configs). Input data (datasets) should be reviewed for PII/sensitivity. No independent security audit mentioned; supply-chain risk depends on Python dependencies (100+ listed). If evaluating private/confidential models, sandbox appropriately.
Alternatives to consider
LMSys Chatbot Arena / LMSYS Leaderboard
Crowdsourced human preference evaluation; lighter-weight but focuses on chat, not specialized benchmarks. No self-hosted option; relies on LMSys infrastructure.
EleutherAI Evaluation Harness
Lightweight Python toolkit for standard benchmarks (MMLU, HellaSwag, etc.). Simpler setup but fewer datasets and no built-in LLM-judge or advanced evaluators.
Hugging Face's Lighteval / Model Evaluation
Integrated into Hugging Face Hub; supports model leaderboards and standard evals. Easier integration if already in HF ecosystem but less flexible for custom pipelines.
Build on opencompass with DEV.co software developers
Start with OpenCompass for standardized, reproducible benchmarking. Deploy locally or leverage CompassHub for leaderboards. Let's discuss your evaluation strategy and infrastructure needs.
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opencompass FAQ
Can I run OpenCompass without a GPU?
How do I evaluate a custom/private model?
What is the cost of evaluating with OpenCompass?
Can I publish results from OpenCompass on a leaderboard?
Software development & web development with DEV.co
DEV.co is a software development agency delivering custom software development services to companies building on open source. Our software developers and web developers design, integrate, and ship production systems — spanning web development, APIs, AI, data, and cloud. If opencompass is part of your ai frameworks roadmap, our team can implement, customize, migrate, and maintain it.
Ready to Evaluate Your LLMs?
Start with OpenCompass for standardized, reproducible benchmarking. Deploy locally or leverage CompassHub for leaderboards. Let's discuss your evaluation strategy and infrastructure needs.