Grok 4.6 vs GPT-5.6 Terra Pro: side-by-side summary

Grok 4.6 and GPT-5.6 Terra Pro are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

Grok 4.6, from SpaceXAI, has a 500,000-token context window and is priced at $2/M tokens input, $6/M tokens output on OpenRouter.

GPT-5.6 Terra Pro, 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

• Grok 4.6: 500,000 tokens
• GPT-5.6 Terra Pro: 1,050,000 tokens

Price

• Grok 4.6: $2/M tokens input, $6/M tokens output
• GPT-5.6 Terra Pro: $1/M tokens input, $6/M tokens output

Provided by

• Grok 4.6: SpaceXAI
• GPT-5.6 Terra Pro: OpenAI

• Grok 4.6 model details, providers and pricing
• GPT-5.6 Terra Pro model details, providers and pricing