What is OpenRouter?

OpenRouter is a service that gives you access to hundreds of AI models — from OpenAI, Anthropic, Google, Meta, DeepSeek, and dozens of others — through one API and one bill. Instead of juggling separate accounts with every AI company, you sign up once and switch models by changing a single line of code.

It is the best-known example of an LLM gateway: a layer that sits between your app and the model providers. Your app talks to OpenRouter, and OpenRouter forwards the request to whichever model you picked.

Why bother with a middleman? A few practical reasons:

• One integration. It follows the same request format as OpenAI, so most tools that speak the standard LLM API shape work with it out of the box.
• Easy comparison. Testing whether Claude, GPT, or an open model handles your task best takes minutes, not days of integration work.
• Fallbacks. If one provider goes down or rate-limits you, OpenRouter can route the request to a backup automatically.

Pricing is pay-as-you-go. You load credits and pay per token, at rates that track what each provider charges directly.

The trade-off is that your requests pass through one more company, which matters if you are handling sensitive data. But for developers who want to experiment across models without managing ten sets of API keys, it has become the default on-ramp.