GPT-5.1 Codex Max vs Claude 4.5 Opus
Detailed comparison of capabilities, features, and performance.
Feature
GPT-5.1 Codex Max
Claude 4.5 Opus
Model Image
AI Lab
OpenAI
Anthropic
Context Size
400,000 tokens
200,000 tokens
Max Output Size
128,000 tokens
64,000 tokens
Frontier Model
Yes
Yes
Vision Support
Yes
Yes
Description
A version of GPT-5.1 optimized for agentic coding tasks in Codex or similar environments.
The latest Opus 4.5 model from Anthropic
Learn more about GPT-5.1 Codex Max
View detailed specifications and capabilities
View model details →Learn more about Claude 4.5 Opus
View detailed specifications and capabilities
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