GPT 5.1 Codex Max API Pricing & Quick Start

Name: GPT 5.1 Codex Max API
Brand: OpenAI

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...

Pricing

Input Price

$1.2500

/ 1M tokens

NT$ 40

Output Price

$10.0000

/ 1M tokens

NT$ 324

Context Window

400K

tokens

💱 USD/NTD = 32.38 · before tax · updated 07/30/2026

Provider	OpenAI
Released	December 2025
Model ID	`openai/gpt-5.1-codex-max`

Technical specifications

Context window

400K tokens

Reasoning

Yes

Input

TextImage

Output

Text

Quick Start

Use GPT 5.1 Codex Max via BazaarLink API — just change the base_url:

Python

from openai import OpenAI

client = OpenAI(
    base_url="https://bazaarlink.ai/api/v1",
    api_key="sk-bl-YOUR_API_KEY",
)

response = client.chat.completions.create(
    model="openai/gpt-5.1-codex-max",
    messages=[{"role": "user", "content": "Hello!"}],
)
print(response.choices[0].message.content)

TypeScript

import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://bazaarlink.ai/api/v1",
  apiKey: "sk-bl-YOUR_API_KEY",
});

const response = await client.chat.completions.create({
  model: "openai/gpt-5.1-codex-max",
  messages: [{ role: "user", content: "Hello!" }],
});
console.log(response.choices[0].message.content);

Why use GPT 5.1 Codex Max via BazaarLink?

✓USD billing (TWD-quoted) + unified invoices — no foreign credit card needed for Taiwan teams
✓OpenAI-compatible API — zero code changes required
✓Automatic failover — multi-provider redundancy for the same model
✓Chinese-language support — local team, instant help

Try Now ← All Models

Frequently Asked Questions

What is GPT 5.1 Codex Max?

How much does the GPT 5.1 Codex Max API cost?

GPT 5.1 Codex Max costs $1.2500 per 1M input tokens and $10.0000 per 1M output tokens when accessed through BazaarLink.

How do I use GPT 5.1 Codex Max with the OpenAI SDK?

Set base_url to "https://bazaarlink.ai/api/v1" and use model ID "openai/gpt-5.1-codex-max". All OpenAI SDK methods (chat.completions, embeddings, streaming) work without code changes.

What is the context window for GPT 5.1 Codex Max?

GPT 5.1 Codex Max supports a context window of 400,000 tokens.

Is GPT 5.1 Codex Max available for free?

GPT 5.1 Codex Max is a paid model. BazaarLink offers free trial credits on registration so you can test it without a credit card.

Relay integrity checks

No integrity-check data is available for this model yet.

BazaarLink Probe verifies endpoints that claim to serve this model and flags behavior that differs from the reference baseline.

View the full integrity report →