Overview
Claude Opus 4.5 vs Grok 4 Fast: side-by-side summary
Claude Opus 4.5 and Grok 4 Fast are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Claude Opus 4.5, from Anthropic, has a 200,000-token context window and is priced at $5/M tokens input, $25/M tokens output on OpenRouter.
Grok 4 Fast, from SpaceXAI, has a 2,000,000-token context window and is priced by the provider serving it on OpenRouter.
- Context window
- Claude Opus 4.5: 200,000 tokens
- Grok 4 Fast: 2,000,000 tokens
- Price
- Claude Opus 4.5: $5/M tokens input, $25/M tokens output
- Grok 4 Fast: Pricing varies by provider
- Provided by
- Claude Opus 4.5: Anthropic
- Grok 4 Fast: SpaceXAI