Claude Opus 5 vs GPT-5.6 Terra: side-by-side summary

Claude Opus 5 and GPT-5.6 Terra are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

Claude Opus 5, 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-5.6 Terra, from OpenAI, has a 1,050,000-token context window and is priced at $1/M tokens input, $6/M tokens output on OpenRouter.

Context window

• Claude Opus 5: 1,000,000 tokens
• GPT-5.6 Terra: 1,050,000 tokens

Price

• Claude Opus 5: $5/M tokens input, $25/M tokens output
• GPT-5.6 Terra: $1/M tokens input, $6/M tokens output

Provided by

• Claude Opus 5: Anthropic
• GPT-5.6 Terra: OpenAI

• Claude Opus 5 model details, providers and pricing
• GPT-5.6 Terra model details, providers and pricing