Protocol filter

Free OpenAI-compatible API routes

An OpenAI-compatible API can reduce integration work when a client accepts a custom base URL and model ID. This page surfaces matching catalog routes without claiming identical feature coverage.

Current shortlist22 active model candidates

Latest provider source check: 2026-07-28.

What this shortlist means

The inclusion rules are visible and intentionally narrow.

  1. 01

    Inclusion rule

    The model protocol is recorded as OpenAI compatible.

  2. 02

    Inclusion rule

    The provider has an active reviewed application profile.

  3. 03

    Inclusion rule

    Each row links to the exact model ID and key path.

Important limit: Compatibility is not equivalence. Streaming, tool calls, structured output, embeddings and Responses API behavior may differ by provider and model.

Matching candidates

Live catalog results with provider evidence dates and the limits you should read before signup.

Model and providerWhy it matchesEvidence and limitsNext steps
GLM-5.2
NVIDIA NIM
z-ai/glm-5.2
OpenAI compatible
Developer access
Official sources: 2026-07-28
Not listed in the official quickstart
Up to 40 RPM; account limits may differ
Independent Canary pending
Qwen3.6 27B
GroqCloud
qwen/qwen3.6-27b
OpenAI compatible
No-card free plan
Official sources: 2026-07-28
Not required for the Free plan
Model and organization specific
Independent Canary pending
DeepSeek R1
SiliconFlow
deepseek-ai/DeepSeek-R1
OpenAI compatible
Starter credits / free-model policy
Official sources: 2026-07-28
Not listed as required for starter access
Model and account specific
Independent Canary pending
GPT-OSS 120B
Cerebras Inference
gpt-oss-120b
OpenAI compatible
Payment-verified starter credits
Official sources: 2026-07-28
Verified payment method required for starter credits
Plan and model specific
Independent Canary pending
Cohere: North Mini Code (free)
OpenRouter
cohere/north-mini-code:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
Free Models Router
OpenRouter
openrouter/free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
Google: Gemma 4 26B A4B (free)
OpenRouter
google/gemma-4-26b-a4b-it:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
Google: Gemma 4 31B (free)
OpenRouter
google/gemma-4-31b-it:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
Google: Lyria 3 Clip Preview
OpenRouter
google/lyria-3-clip-preview
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
Google: Lyria 3 Pro Preview
OpenRouter
google/lyria-3-pro-preview
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
LiquidAI: LFM2.5-2.6B (free)
OpenRouter
liquid/lfm-2.5-2.6b:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron 3 Nano 30B A3B (free)
OpenRouter
nvidia/nemotron-3-nano-30b-a3b:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron 3 Nano Omni (free)
OpenRouter
nvidia/nemotron-3-nano-omni-30b-a3b-reasoning:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron 3 Super (free)
OpenRouter
nvidia/nemotron-3-super-120b-a12b:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron 3 Ultra (free)
OpenRouter
nvidia/nemotron-3-ultra-550b-a55b:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron 3.5 Content Safety (free)
OpenRouter
nvidia/nemotron-3.5-content-safety:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron 3.5 Lightning (free)
OpenRouter
nvidia/nemotron-3.5-lightning:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron Nano 12B 2 VL (free)
OpenRouter
nvidia/nemotron-nano-12b-v2-vl:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
NVIDIA: Nemotron Nano 9B V2 (free)
OpenRouter
nvidia/nemotron-nano-9b-v2:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
OpenAI: gpt-oss-20b (free)
OpenRouter
openai/gpt-oss-20b:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
Poolside: Laguna S 2.1 (free)
OpenRouter
poolside/laguna-s-2.1:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented
Poolside: Laguna XS 2.1 (free)
OpenRouter
poolside/laguna-xs-2.1:free
OpenAI compatible
Official zero-priced route
Official sources: 2026-07-28
Not required to create a key
OpenRouter free-tier limits
Model route documented