GPT-5.1 Codex vs Claude 4.5 Sonnet
Detailed comparison of capabilities, features, and performance.
Feature
GPT-5.1 Codex
Claude 4.5 Sonnet
Model Image
AI Lab
OpenAI
Anthropic
Context Size
400,000 tokens
1,000,000 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 Claude 4.5 Sonnet model from Anthropic with a 1M token context window.
Learn more about GPT-5.1 Codex
View detailed specifications and capabilities
View model details →Learn more about Claude 4.5 Sonnet
View detailed specifications and capabilities
View model details →More model comparisons
Try both models in your workspace
Access both GPT-5.1 Codex and Claude 4.5 Sonnet in a single workspace without managing multiple API keys.
Create your workspace