OpenAI-compatible base URLs cheat sheet

Published 2026-10-14 · Updated 2026-10-26

Almost every provider now exposes an OpenAI-compatible endpoint. The API key changes; the code doesn’t. Here’s the table.

Provider	Base URL	Env var
OpenAI	`https://api.openai.com/v1`	`OPENAI_API_KEY`
OpenRouter	`https://openrouter.ai/api/v1`	`OPENROUTER_API_KEY`
xAI	`https://api.x.ai/v1`	`XAI_API_KEY`
DeepSeek	`https://api.deepseek.com/v1`	`DEEPSEEK_API_KEY`
Z.ai (GLM)	`https://api.z.ai/api/paas/v4`	`ZAI_API_KEY`
MiniMax	`https://api.minimax.io/v1`	`MINIMAX_API_KEY`
Moonshot (intl)	`https://api.moonshot.ai/v1`	`MOONSHOT_API_KEY`
Moonshot (CN)	`https://api.moonshot.cn/v1`	`MOONSHOT_API_KEY`
DashScope (intl)	`https://dashscope-intl.aliyuncs.com/compatible-mode/v1`	`DASHSCOPE_API_KEY`
Mistral	`https://api.mistral.ai/v1`	`MISTRAL_API_KEY`
Groq	`https://api.groq.com/openai/v1`	`GROQ_API_KEY`
Together	`https://api.together.xyz/v1`	`TOGETHER_API_KEY`
Fireworks	`https://api.fireworks.ai/inference/v1`	`FIREWORKS_API_KEY`
Cerebras	`https://api.cerebras.ai/v1`	`CEREBRAS_API_KEY`
NVIDIA	`https://integrate.api.nvidia.com/v1`	`NVIDIA_API_KEY`
Google (OpenAI-compat)	`https://generativelanguage.googleapis.com/v1beta/openai/`	`GEMINI_API_KEY`

The one gotcha: Anthropic

Anthropic’s native API isn’t OpenAI-shaped. For Claude through OpenAI-style code, either use OpenRouter (anthropic/claude-sonnet-5) or a provider with an Anthropic-compat surface.

Trailing details that break configs

Groq needs openai/v1, the most-forgotten path segment in the table.
Google’s compat path ends in a slash and lives under v1beta/openai/.
DashScope differs by region. -intl for the Singapore console, plain dashscope.aliyuncs.com for China.
Model ids change shape. Direct APIs use bare names (grok-5-mini); OpenRouter uses vendor/model.

When a client asks for “custom OpenAI provider” or “OpenAI-compatible”, this table is all it needs: base URL, key, model id.