API Relay · OpenAI Compatible
API Relay Guide: Free Models, OpenAI-Compatible Calls, and China Access
A practical guide for API relay, API proxy, API VPN, free model routing, and OpenAI-compatible LLM endpoints.
Three common API relay routes
Route 1
Official API + OpenAI SDK
DeepSeek, Qwen, Hunyuan, and NVIDIA Build can be used with OpenAI-compatible or similar SDK patterns.
Route 2
Free-tier aggregation
FreeLLMAPI, LiteLLM, and One-API can unify multiple free tiers for experiments and internal tools.
Route 3
Commercial relay
One key for GPT, Claude, Gemini, DeepSeek, and Qwen, with stronger billing, logs, fallback, and support.
Recommended pages
DeepSeek APISignup credits and low-cost OpenAI-compatible calls.Qwen APIAlibaba Bailian credits and compatible-mode endpoint.Tencent Hunyuan APITencent Cloud credits and China-friendly access.NVIDIA Build APINIM free API access for developer experiments.FreeLLMAPIOpen-source GitHub project for free LLM API aggregation.