GPT-5.1 Codex Max
GPT-5.1 Codex Max is a OpenAI model listed in the NextModel catalog for image understanding, multimodal chat workloads. Its listed price is $1.25 / 1M tokens input and $10 / 1M tokens output, with a 400k token context window.
What is GPT-5.1 Codex Max in NextModel?
GPT-5.1 Codex Max is a OpenAI model listed in the NextModel catalog for image understanding, multimodal chat workloads. Its listed price is $1.25 / 1M tokens input and $10 / 1M tokens output, with a 400k token context window.
GPT-5.1 Codex Max via NextModel: 400k-token context; $1.25 / 1M tokens in / $10 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.
Best use cases
- image understanding
- multimodal chat
OpenAI-compatible code example
curl https://api.nextmodel.app/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $NEXTMODEL_API_KEY" \
-d '{"model":"openai/gpt-5.1-codex-max","messages":[{"role":"user","content":"Reply with OK."}]}'Switching models only changes the model field.
Similar alternatives
GPT-5.2 via NextModel: 400k-token context; $1.75 / 1M tokens in / $14 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.
GPT-5.1 via NextModel: 400k-token context; $1.25 / 1M tokens in / $10 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.
GPT-5.1 Codex via NextModel: 400k-token context; $1.25 / 1M tokens in / $10 / 1M tokens out per 1M tokens. Capabilities: streaming, tool, json.
Reading
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FAQ
GPT-5.1 Codex Max API questions
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