Overview
Claude Sonnet 4.5 vs Gemini 2.5 Flash Preview 09-2025: side-by-side summary
Claude Sonnet 4.5 and Gemini 2.5 Flash Preview 09-2025 are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Claude Sonnet 4.5, from Anthropic, has a 1,000,000-token context window and is priced at $3/M tokens input, $15/M tokens output on OpenRouter.
Gemini 2.5 Flash Preview 09-2025, from Google, has a 1,048,576-token context window and is priced by the provider serving it on OpenRouter.
- Context window
- Claude Sonnet 4.5: 1,000,000 tokens
- Gemini 2.5 Flash Preview 09-2025: 1,048,576 tokens
- Price
- Claude Sonnet 4.5: $3/M tokens input, $15/M tokens output
- Gemini 2.5 Flash Preview 09-2025: Pricing varies by provider
- Provided by
- Claude Sonnet 4.5: Anthropic
- Gemini 2.5 Flash Preview 09-2025: Google