Polyrouter

What Polyrouter is

Polyrouter is an open-source LLM gateway that gives clients a single endpoint for connecting to multiple model providers. It supports explicit model selection, header-based rules, routing tiers, and optional automatic routing. Ordered fallback chains and provider-specific circuit breakers can keep requests moving when a provider degrades. Spend budgets can be set globally or per agent for daily, weekly, or monthly windows, with alerts or request blocking at a threshold.

The gateway supports OpenAI- and Anthropic-compatible APIs and translates requests between the two protocols. Provider connections can use API keys, OAuth subscriptions, compatible custom endpoints, or self-hosted local models such as Ollama, LM Studio, and llama.cpp. Clients that accept a configurable base URL and API key can connect, including compatible SDKs. Logs contain metadata by default; prompt and response capture is an opt-in self-hosted setting that is off by default. Credentials are encrypted at rest, and user-supplied URLs are checked against private and metadata address ranges. Self-hosting requires Docker with Compose v2 and runs the SPA, API, and proxy with PostgreSQL 16 and Redis. Polyrouter is maintained by Anthony Izzo under the AGPL-3.0 license.

Who it suits

Polyrouter suits developers and teams connecting applications or agents to multiple model providers through a configurable API endpoint. It is a fit for users who want routing, fallback, and spend controls and are prepared to self-host with Docker Compose v2.

Limits

Self-hosting is free, but provider charges are paid directly. Deployment requires Docker with Compose v2, PostgreSQL 16, and Redis.

Getting started

1. Visit https://polyrouter.app/.
2. Set up Docker with Compose v2.
3. Deploy the SPA, API, and proxy alongside PostgreSQL 16 and Redis.
4. Connect provider options using API keys, OAuth subscriptions, compatible custom endpoints, or supported local models.
5. Configure a client with the gateway's base URL and an API key.

Verdict

Choose Polyrouter if you need one endpoint for multiple model providers and want routing, fallback, and budget controls in a free, self-hosted gateway. It requires a Docker Compose deployment and separate provider charges; managed cloud hosting is not yet described as available.