Free OpenAI-Compatible API — Drop-in ChatGPT API Replacements

Use the OpenAI SDK against free providers — Groq, Gemini, Mistral, Cohere, OpenRouter, and 25+ more. No OpenAI bill, no credit card.

🌐 Browse all OpenAI-compatible free APIs at freellms.org

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What is a Free OpenAI-Compatible API?

Any API that accepts the OpenAI Chat Completions request format (/v1/chat/completions, messages, model, apiKey). You can swap https://api.openai.com/v1 for any provider below and your code keeps working — for free.

Full directory of OpenAI-compatible providers: freellms.org

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OpenAI-Compatible Free API Directory

Provider	Base URL	Free Tier	OpenAI-Compatible
Groq	https://api.groq.com/openai/v1	30 RPM, 14,400 RPD	✅ Full
Google Gemini	https://generativelanguage.googleapis.com/v1beta	15 RPM, 1,500 RPD	✅ Full
Mistral AI	https://api.mistral.ai/v1	Free tier	✅ Full
Cohere	https://api.cohere.com/v2	20 RPM	✅ Full
OpenRouter	https://openrouter.ai/api/v1	1K RPD	✅ Full
NVIDIA NIM	https://integrate.api.nvidia.com/v1	Free tier	✅ Full
GitHub Models	https://models.github.ai/inference	Free tier	✅ Full
Cloudflare Workers AI	https://api.cloudflare.com/client/v4/accounts/{id}/ai/run	10K neurons/day	✅ Full
Cerebras	https://api.cerebras.ai/v1	5 RPM	✅ Full
Hugging Face	https://router.huggingface.co/v1	Free tier	✅ Full
SambaNova	https://api.sambanova.ai/v1	20 RPM	✅ Full
LLM7.io	https://api.llm7.io/v1	30 RPM	✅ Full
Z AI (Zhipu)	https://open.bigmodel.cn/api/paas/v4	Free tier	✅ Full
DeepSeek	https://api.deepseek.com/v1	Free tier	✅ Full

All base URLs + free API keys: freellms.org

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Quick Start — Replace OpenAI with a Free API in 30 Seconds

Python (OpenAI SDK)

from openai import OpenAI

# Before: paid OpenAI
# client = OpenAI(api_key="sk-...")

# After: free Groq (no credit card)
client = OpenAI(
    base_url="https://api.groq.com/openai/v1",   # free OpenAI-compatible API
    api_key="YOUR_FREE_KEY",                      # get at freellms.org
)

response = client.chat.completions.create(
    model="llama-3.3-70b-versatile",              # free model
    messages=[{"role": "user", "content": "Hello, free ChatGPT!"}],
)
print(response.choices[0].message.content)

Codex CLI

export OPENAI_BASE_URL="https://api.groq.com/openai/v1"
export OPENAI_API_KEY="your-free-key"            # freellms.org
codex --model "llama-3.3-70b-versatile"

Cursor

Settings → Models → Add Model
  Model name: llama-3.3-70b-versatile
  Base URL: https://api.groq.com/openai/v1
  API key: your-free-key                        # freellms.org

Claude Code

export ANTHROPIC_BASE_URL="https://openrouter.ai/api"
export ANTHROPIC_AUTH_TOKEN="sk-or-v1-your-key"  # openrouter.ai/keys
export ANTHROPIC_API_KEY=""

Step-by-step config for every tool: freellms.org

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Why use a free OpenAI-compatible API?

• Drop-in replacement — same SDK, same request format, zero code changes
• No OpenAI bill — permanently free tiers, not trial credits
• No credit card — most providers issue keys on email signup
• Multi-provider — switch Groq → Gemini → Mistral by changing one URL
• Works everywhere — Cursor, Codex, Claude Code, Aider, Cline, Open WebUI

Browse all OpenAI-compatible providers, get free keys, and copy config snippets at freellms.org.

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Related Resources

• Free LLM API keys
• Free AI proxy gateway
• Free LLM models
• Awesome free AI agents
• Awesome free LLM APIs

License

MIT — provider data sourced from freellms.org, updated daily.