Why I Built Yet Another LLM API Gateway

I remember sitting at my desk late on a Friday night, staring at a rate limit error from OpenAI.

I was building a small side project - a summarization tool - and had just hit my Tier 1 limits. My immediate thought was, "Fine, I'll just swap to Anthropic for the weekend so I can keep coding."

But that wasn't a one-minute job. I had to:

1. Create a new Anthropic account.
2. Add a minimum $5 balance (another credit card charge).
3. Swap out the openai Python SDK for the anthropic SDK.
4. Rewrite my message formatting logic because the two SDKs handle system prompts completely differently.
5. Update all my error handling.

By the time I was done, I had lost two hours of deep work.

The Fragmented API Nightmare

As developers, we are living in the golden age of AI models. But we are also living in the dark ages of API fragmentation.

Every month, a new model drops that is faster, cheaper, or smarter. DeepSeek, Claude, Gemini, GPT-5.6 Sol - the options are incredible. But actually using them requires managing half a dozen different API keys, keeping track of scattered billing dashboards, and constantly tweaking application logic to support different provider quirks.

You end up writing more code to manage the LLMs than you do building your actual product.

The Solution: RouteLM

I built RouteLM because I wanted a magic endpoint. I wanted to write my application code exactly once, using the standard OpenAI SDK that every library already supports, and never touch it again.

If Claude goes down, I wanted the endpoint to silently failover to GPT-5.6 Sol without my app throwing a 500 error. If a cheap, open-source model like Llama 3 is good enough for a simple classification task, I wanted to route it there automatically to save pennies, without writing complex routing logic myself.

RouteLM is the tool I wished I had that Friday night. It provides:

• One API Key: Access all top-tier models through a single key.
• One Billing Dashboard: No more scattered $5 deposits across five different providers.
• True Drop-In Compatibility: Just change your base_url to https://routelm.dev/v1 and you are done. It works perfectly with Cursor AI, LangChain, and Continue.dev right out of the box.

We aren't trying to be the gateway with the most models. We are trying to be the gateway with the best developer experience for the models you actually use in production.

If you are tired of juggling API keys, give RouteLM a try. You get 50,000 free tokens every month to test it out - no credit card required.

Happy building.