GPT-5.1-Codex-Max
OPENAI Developer Architecture Profile
Intelligence (ELO)1506Chatbot Arena Verified
Max Context Limit400,000Max Out: 128,000 tokens
Prompt Caching90% OFF$0.13 / 1M cached
Standard API / 1M$11.25🧠 Deep Reasoner
Model Capabilities & Contract SLAs
- Coding & Logic
- Fictional
- Reasoning
- Agentic
- 📋 Strict JSON Schema
- 🛠️ Native Tool Calling
- 🧠 Extended Test-Time Reasoning
GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic...
Granular Pricing Matrix
Input Tokens (Standard Prompt)$1.25 / 1M
⚡ Cached Input (Prompt Cache Read)90% OFF$0.13 / 1M
Output Tokens (Completion)$10.00 / 1M
Pricing data via OpenRouter. Sync: 10/2/2026
Evaluate Competitors
VS Engine MatchupGPT-5.1-Codex-Max vs Google: Gemini 3.8 Flash (batch)VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.6 Terra Pro (batch)VS Engine MatchupGPT-5.1-Codex-Max vs Google: Nano Banana 2 (Gemini 3.1 Flash Image)VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.3-CodexVS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.2-CodexVS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT Astra Latest