Claude Opus 4.6 vs GPT-5.1-Codex-Max: side-by-side summary

Claude Opus 4.6 and GPT-5.1-Codex-Max are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

Claude Opus 4.6, from Anthropic, has a 1,000,000-token context window and is priced at $5/M tokens input, $25/M tokens output on OpenRouter.

GPT-5.1-Codex-Max, from OpenAI, has a 400,000-token context window and is priced at $1.25/M tokens input, $10/M tokens output on OpenRouter.

Context window

• Claude Opus 4.6: 1,000,000 tokens
• GPT-5.1-Codex-Max: 400,000 tokens

Price

• Claude Opus 4.6: $5/M tokens input, $25/M tokens output
• GPT-5.1-Codex-Max: $1.25/M tokens input, $10/M tokens output

Provided by

• Claude Opus 4.6: Anthropic
• GPT-5.1-Codex-Max: OpenAI

• Claude Opus 4.6 model details, providers and pricing
• GPT-5.1-Codex-Max model details, providers and pricing