Grok 4.6 vs Claude Opus 5 (Fast): side-by-side summary

Grok 4.6 and Claude Opus 5 (Fast) 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.

Claude Opus 5 (Fast), from Anthropic, has a 1,000,000-token context window and is priced at $10/M tokens input, $50/M tokens output on OpenRouter.

Context window

• Grok 4.6: 500,000 tokens
• Claude Opus 5 (Fast): 1,000,000 tokens

Price

• Grok 4.6: $2/M tokens input, $6/M tokens output
• Claude Opus 5 (Fast): $10/M tokens input, $50/M tokens output

Provided by

• Grok 4.6: SpaceXAI
• Claude Opus 5 (Fast): Anthropic

• Grok 4.6 model details, providers and pricing
• Claude Opus 5 (Fast) model details, providers and pricing