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OpenAIAvailable on TokenCenter

GPT-5.1-Codex-Max

openai/gpt-5.1-codex-max

GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks.

Key facts

Input price
$1.25 / 1M tokens
Output price
$10.00 / 1M tokens
Context window
400K tokens
Max output
128K tokens
Accepts
Text, Images
Returns
Text

Example: 1,000 requests with 1,000 input and 500 output tokens each would cost about $6.25 (1M input tokens × $1.25 + 0.5M output tokens × $10.00). Estimate your own usage.

Prices are the provider’s own per-token rates with zero markup, from our price list as of Oct 18, 2026. If a call has extra provider charges (images, audio, web search, cached prompts), you pay the reported cost.

Get API keyTry in chatCompare

Call it from your code

curl https://api.tokenctr.com/v1/chat/completions \
  -H "Authorization: Bearer $TOKENCENTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "openai/gpt-5.1-codex-max", "messages": [{"role": "user", "content": "Hello!"}]}'

Works with any OpenAI-compatible SDK: set the base URL to https://api.tokenctr.com/v1. Quickstart

Supported request parameters

include_reasoningmax_completion_tokensreasoningreasoning_effortresponse_formatseedstructured_outputstool_choicetoolsverbosity