OpenAI: GPT-5.1-Codex-Max

Public pricingLarge memory芖芚深い思考ツヌル利甚

OpenAI: GPT-5.1-Codex-Max は マルチモヌダル モデルで、コヌディング、゜フトりェア開発、゚ヌゞェント業務 に向いおいたす。マルチモヌダル入力凊理、高いコヌディング性胜、400K tokensのコンテキスト、バランス型コストの特性を組み合わせ、コヌディング、゜フトりェア開発、゚ヌゞェント業務 で安定した動䜜を支えたす。粟床・文脈・制埡 が重芁な堎面に合っおおり、安定した出力、柔軟な導入、拡匵性を求めるチヌムに実甚的です。 安定した応答、長い文脈凊理、そしお詊䜜から本番たで広く䜿える柔軟さが必芁な堎面で圹立ちたす。 安定した応答、長い文脈凊理、そしお詊䜜から本番たで広く䜿える柔軟さが必芁な堎面で圹立ちたす。 安定した応答、長い文脈凊理、そしお詊䜜から本番たで広く䜿える柔軟さが必芁な堎面で圹立ちたす。

Input

$1.25/1M

Output

$10.00/1M

Cached

$0.13/1M

Batch

$0.63/1M

Calculate your GPT-5.1-Codex-Max bill.

Set your workload — see cost at your exact volume.

What would GPT-5.1-Codex-Max cost you?

Adjust the workload to see your monthly bill.

1,00010,00050,000250,0001M10M

Technical specifications

GPT-5.1-Codex-Max at a glance.

Memory

400,000

tokens

Max reply

128,000

tokens

Memory tier

Large

an entire book or large codebase

Tokenizer

tiktoken-o200k

Released

Dec 2025

Training cutoff

Jul 2025

Availability

Public pricing

Status

active

What it can do

Capabilities & limits.

  • Understands images
  • Deep step-by-step thinking
  • Uses tools / calls functions
  • Strict JSON output
  • Streams replies
  • Fine-tunable on your data

When to pick GPT-5.1-Codex-Max

  • Multi-step reasoning, research agents, or hard math.
  • Screenshot analysis, image understanding, or document OCR.
  • Agentic workflows that call tools or APIs.
  • Long documents, full codebases, or extensive chat histories.

When to look elsewhere

  • Very latency-sensitive, real-time apps where every millisecond counts.

Alternatives

Similar models to compare.

FAQ

GPT-5.1-Codex-Max — the questions we see most.

Pricing, capabilities, alternatives — generated from the same data that powers the calculator above.

Get instant answers from our AI agent

At a typical workload of 50,000 conversations a month with 1,500-token prompts and 800-token replies, GPT-5.1-Codex-Max costs roughly $494 per month. Input is $1.25 /1M tokens and output is $10.00 /1M tokens.
GPT-5.1-Codex-Max has a 400,000-token context window (large memory — an entire book or large codebase). That means you can fit about 75,000 words of input and history in a single call.
Beyond text generation, GPT-5.1-Codex-Max supports understanding images, deep step-by-step reasoning, calling functions / tools, strict JSON output, fine-tuning on your own data. It streams replies by default.
GPT-5.1-Codex-Max was released in December 2025, with training data cut off around July 2025.

Still unsure?

Compare GPT-5.1-Codex-Max against 100+ other models.

Open the full wizard — pick a use case, set your usage, and see side-by-side monthly costs in under a minute.

Open the comparison wizard