LLM Reference

Router profile

RouteLLM

LMSYS (lm-sys)

Visit RouteLLM
RouterFresh · 2026-06-08
Open-source LLM routing framework from LMSYS that routes simpler queries to a cheaper weak model and harder ones to a stronger frontier model, achieving 35–85% cost reduction on benchmarks.

Type

Router

Lead directory segment

Pricing model

Free OSS

Model count pending

Hosting

Self-hosted

Self-host option available

Data retention

Zero retention

Verify for production policy

At a glance

Decision mechanism
Predictive learnedCascade
Optimizes for
CostQuality
Routing scope
Binary pair
Decision timing
Pre-generation
Deployment path
Proxy in path
Openness
Open source
API compatibility
OpenAI

Routes to these providers

OpenAI API

OpenAI's AI platform offers a comprehensive suite of advanced technologies designed to revolutionize various applications across industries. At its core, the platform features powerful natural language processing capabilities for generating human-like text, image generation through models like DALL-E, and automatic speech recognition with Whisper. These functionalities are complemented by robust predictive analytics tools that enable businesses to forecast user behavior and automate customer interactions through sophisticated chatbots. The platform's APIs facilitate seamless integration, allowing users to develop custom solutions that leverage machine learning for analyzing large datasets, automating repetitive tasks, and enhancing decision-making processes. One of the platform's key strengths lies in its flexibility and customization options. Users can fine-tune models to better align with their specific needs, ensuring that AI outputs are tailored to individual organizational requirements. This adaptability, combined with the platform's advanced security features such as data encryption and multi-factor authentication, makes it a powerful tool for businesses looking to innovate rapidly and maintain a competitive edge. By automating knowledge-based tasks and providing personalized recommendations and insights, the platform significantly enhances operational efficiency and customer experience, enabling organizations to scale operations effectively and foster customer loyalty .

Anthropic

Creator of Claude AI models, accessed via the Anthropic API and the Anthropic Console (console.anthropic.com). The Console hosts the Workbench prompt playground, API keys, usage analytics, and team billing.

Google AI Studio

Google AI Studio is a model prototyping environment and API access point for Gemini models, offering an inference playground for developers to test and build AI applications.

GCP Vertex AI

Google Cloud Vertex AI is a comprehensive machine learning platform that provides end-to-end solutions for developing, deploying, and managing AI models. The platform offers a unified interface that integrates various tools and services, enabling users to efficiently handle the entire machine learning lifecycle. Key features include AutoML capabilities for building custom models with minimal coding, a managed notebook environment for prototyping, and robust MLOps tools for model monitoring and versioning. Vertex AI supports both pre-trained models and custom training, making it versatile for a wide range of applications such as natural language processing, image recognition, and predictive analytics. The platform's design focuses on increasing productivity and accelerating time-to-market for AI solutions. By consolidating multiple AI tools into a single ecosystem, Vertex AI reduces manual effort and enhances collaboration among data scientists and engineers. Its scalable architecture allows organizations to efficiently manage large datasets and complex models, while the pay-as-you-go pricing model makes it accessible for businesses of all sizes. Additionally, Vertex AI's integration with popular open-source frameworks like TensorFlow and PyTorch enables users to leverage existing models and tools, fostering innovation and facilitating the development of customized AI applications tailored to specific business needs.

Pricing & data handling

Open-source research framework from LMSYS (creators of Chatbot Arena). No hosted service; you supply your own model API keys. Router models trained on GPT-4 / Mixtral pair; generalizes to other strong/weak pairs via --strong-model and --weak-model flags.

Retention
Zero retention
Self-host
Available
Last checked
2026-06-08

Sources & freshness

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