For Devs, Open Source

Find the Best LLM
for Your Project.

Langmuse is an open-source AI benchmarking platform that helps you evaluate, compare, and select the right LLM model, based on your actual use case, not marketing specs.

Open Source on GitHub

30+

LLM Models Supported

50+

Built-in Benchmarks

100%

Open Source

Self

Hostable

Compare Any Model, Anywhere

Langmuse supports all major LLM providers out of the box.

GPT-4o

OpenAI

Claude 3.5 Sonnet

Anthropic

Gemini 1.5 Pro

Google

Mistral Large

Mistral AI

LLaMA 3.1 405B

Meta

Command R+

Cohere

Grok 2

xAI

30+ More

All Providers

Purpose-Built for Developers

Stop guessing which model is best. Langmuse gives you data-driven answers.

Multi-Model Benchmarking

Run head-to-head comparisons across GPT-4o, Claude 3.5, Gemini, Mistral, LLaMA, and 30+ other models on your own task types.

Task-Specific Evaluation

Benchmark models on the exact tasks your product needs, code generation, summarization, reasoning, retrieval, function calling, and more.

Cost vs. Performance Analysis

Visualize the price-to-performance tradeoff across every model. Find the optimal model that balances quality and API cost for your budget.

Custom Test Suites

Define your own evaluation criteria, rubrics, and golden datasets. Run automated test suites and get reproducible scores you can trust.

Version Tracking

Track how model performance evolves over time as providers update their models. Get alerted when your top-performing model drops in quality.

Open Source & Self-Hostable

Fully open source on GitHub. Run Langmuse in your own infrastructure for complete data privacy and no vendor lock-in.

Stop Guessing. Start Benchmarking.

Open source, self-hostable, and free. Start comparing LLMs on your own tasks in minutes.