What Is OpenRouter?
OpenRouter is an API gateway that routes requests to any LLM — OpenAI, Anthropic, Google, Meta, Mistral, and dozens of open-source models. One API key, one endpoint, 100+ models. It's OpenAI-compatible, so switching from direct OpenAI API requires changing only the base URL.
Smart Routing and Fallbacks
Configure primary and fallback models. If Claude is down, automatically route to GPT-4. Route by cost (cheapest model that meets quality threshold), latency (fastest response), or capability (use specific models for specific tasks). This resilience is hard to build yourself.
Integration Guide
Replace your OpenAI base URL with https://openrouter.ai/api/v1. Set your OpenRouter API key. Specify the model with provider prefix: anthropic/claude-3.5-sonnet, openai/gpt-4, google/gemini-pro. Streaming, function calling, and vision all work through the unified API.
Cost Optimization
OpenRouter shows real-time pricing for every model. Route simple tasks to cheap models (Gemini Flash, GPT-4 Mini) and complex tasks to premium models (Claude Opus, GPT-4). This tiered approach can reduce AI costs by 60-80% compared to using premium models for everything.
Best Use Cases
A/B testing different models for quality. Building apps that let users choose their AI model. Fallback routing for production reliability. Cost optimization through intelligent routing. Rapid prototyping with different models without managing multiple accounts.
Conclusion
OpenRouter simplifies multi-model AI development. Instead of managing API keys and SDKs for each provider, use one endpoint. The routing and fallback capabilities alone justify the small markup. Essential for any production AI application that needs reliability.