AI Model APIs
AI Model APIsProviders
AI Model APIs

The complete platform for comparing AI models. Find pricing, capabilities, and the perfect model for your use case.

contact@aimodelapis.com

Resources

  • AI Models APIs
  • Providers

About

  • About
  • Contact
  • Privacy Policy
  • Terms of Service

© 2026 AI Model APIs. All rights reserved.

Back to Models
OpenRouter

GPT-5.1-Codex-Max API

OpenRouter
About

Build advanced reasoning agents with GPT-5.1-Codex-Max, a specialized AI model optimized for complex logic and chain-of-thought tasks. This model delivers cost-effective pricing at $1.10/1M input and $9.00/1M output tokens, native tool calling support. Access GPT-5.1-Codex-Max via the OpenRouter API with up to 128K output tokens.

Capabilities

Input Modalities

textimage

Output Modalities

text
Reasoning
Yes
Structured Output
Yes
Tool Use
Yes
WeightsClosed
Temperature
Adjustable
Attachment
Supported
Limits
Context Window
400K

Tokens

Input Limit
400K

Tokens

Max Output
128K

Tokens

Pricing

Standard (per 1M tokens)

Input
$1.10
Output
$9.00

Caching (per 1M tokens)

Read
$0.11
Frequently Asked Questions

GPT-5.1-Codex-Max by OpenRouter costs $1.10 per 1M input tokens and $9.00 per 1M output tokens. Cached reads cost $0.11 per 1M tokens.

Model Details
ID
openai/gpt-5.1-codex-max
Provider
OpenRouter
Family
gpt-codex
Release Date
Nov 13, 2025
Knowledge Cutoff
Sep 30, 2024
API Integration
NPM Package
@openrouter/ai-sdk-provider
Environment Variables
OPENROUTER_API_KEY
API Base URL
https://openrouter.ai/api/v1
Documentation