GPT-5.1-Codex-Max

OPENAI Developer Architecture Profile

Intelligence (ELO)1506Chatbot Arena Verified

Max Context400,000Tokens

API Cost / 1M$11.25Blended Prompt + Completion

Model Capabilities

Coding & Logic
Fictional

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 (Prompt)$1.25 / 1M

Output Tokens (Completion)$10.00 / 1M

Pricing data via OpenRouter. Sync: 4/30/2026

Evaluate Competitors

VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.3-Codex VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.2-Codex VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-4o (2024-08-06)VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.5 Pro VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.4 Pro VS Engine MatchupGPT-5.1-Codex-Max vs OpenAI: GPT-5.2 Pro