Setup guide - Documented by Aider
Use OpenAI in Aider
Aider works with OpenAI's models via OPENAI_API_KEY (or --api-key openai=<key>) and aider --model <model-name> for any OpenAI model.
Last verified 4 steps2 official sources
Steps
- Step 1.
Install aider.
Terminalpython -m pip install aider-install aider-install - Step 2.
Configure your API key.
Terminalexport OPENAI_API_KEY=<key> # Mac/Linux setx OPENAI_API_KEY <key> # Windows, restart shell after setx - Step 3.
Start aider in your codebase with an OpenAI model. Aider documents that aider --model <model-name> works for any other OpenAI model.
Terminal# Change directory into your codebase cd /to/your/project aider --model <model-name> - Step 4.
List models available from OpenAI.
Terminalaider --list-models openai/
Caveats
- Aider's OpenAI page examples are older models (o3-mini, o1-mini, gpt-4o); the GPT-6 ids come from OpenAI's model catalog. Confirm with aider --list-models openai/.
- Reasoning models may need aider's reasoning model settings (and --reasoning-effort) if you see temperature or system prompt errors.
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FAQ
How do I use OpenAI in Aider?
Aider works with OpenAI's models via OPENAI_API_KEY (or --api-key openai=<key>) and aider --model <model-name> for any OpenAI model.
Which OpenAI model ids work in Aider?
The official docs read for this guide list gpt-6.1-sol, gpt-6-astra and gpt-6-luna.
Is this an official OpenAI and Aider setup?
Aider documents this setup in its own docs. It was last checked against 2 official pages on October 17, 2026.
Sources
Last verified against 2 official pages.
- aider.chathttps://aider.chat/docs/llms/openai.html
- developers.openai.comhttps://developers.openai.com/api/docs/models
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