OpenRouter alternatives for routing OpenAI and Anthropic requests

If you want OpenRouter-style routing for OpenAI and Anthropic requests, the main alternatives fall into a few buckets:

1) API gateways / unified model routers

These sit between your app and multiple LLM providers.

• LiteLLM

  • Very popular OpenAI-compatible proxy/router.
  • Supports OpenAI, Anthropic, Azure, Bedrock, Gemini, Together, etc.
  • Good if you want load balancing, fallbacks, budgets, retries, logging.
  • Can be self-hosted.

• Portkey

  • LLM gateway with routing, fallbacks, observability, guardrails.
  • OpenAI-compatible interface.
  • Good for production teams.

• Helicone

  • Primarily observability, but also acts as a proxy layer.
  • Useful if you want logging, analytics, cost tracking, and some routing.

• LangChain / LangGraph model routing

  • Not a drop-in OpenRouter replacement, but can route calls across providers in app logic.
  • Better for application-level orchestration than infra-level routing.

2) Cloud provider “model marketplaces”

These are not exact OpenRouter replacements, but they unify access to many models.

• AWS Bedrock

  • Access to Anthropic and some other providers/models through AWS.
  • Strong for enterprise and governance.

• Google Vertex AI

  • Broad model access depending on region/product offerings.
  • Good if you are already on GCP.

• Azure AI Foundry / Azure OpenAI

  • Best if you want enterprise controls and already use Azure.
  • More focused on Azure-hosted offerings than multi-provider routing.

3) Self-hosted proxies / custom routing

If you want maximum control:

• LiteLLM Proxy is the most common choice.
• You can also build a simple router:
  • send to OpenAI for some tasks
  • Anthropic for others
  • fallback on error/timeout
  • enforce per-model budgets and rate limits

Best options by use case

• Closest to OpenRouter: LiteLLM or Portkey
• Best self-hosted: LiteLLM
• Best observability + gateway: Helicone or Portkey
• Best enterprise cloud-native: Bedrock / Vertex / Azure
• Best if you only need app-level routing: LangChain/LangGraph

Important note

OpenAI and Anthropic have different API shapes, especially for:

• tool use
• system messages
• streaming
• JSON mode / structured outputs
• vision support
• retry/error semantics

So if you want one unified interface, choose a gateway that already normalizes these differences.

If you want, I can also give you:

1. a comparison table of OpenRouter vs LiteLLM vs Portkey vs Helicone, or
2. a recommended architecture for routing OpenAI + Anthropic in production.