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  1. Home
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  3. Compare

Claude Sonnet 4.5 vs Gemini 2.5 Flash Preview 09-2025

Compare Claude Sonnet 4.5 from Anthropic and Gemini 2.5 Flash Preview 09-2025 from Google on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the OpenRouter API.

Favicon for anthropic
Claude Sonnet 4.5
Favicon for google
Gemini 2.5 Flash Preview 09-2025
Favicon for anthropic
Claude Sonnet 4.5
Favicon for google
Gemini 2.5 Flash Preview 09-2025

Overview

Claude Sonnet 4.5
Author
Anthropic
Gemini 2.5 Flash Preview 09-2025
Author
Google
Claude Sonnet 4.5
Context length
1Mtokens
Gemini 2.5 Flash Preview 09-2025
Context length
1.05Mtokens
Claude Sonnet 4.5
Reasoning
Gemini 2.5 Flash Preview 09-2025
Reasoning
Claude Sonnet 4.5
Input modalities
Gemini 2.5 Flash Preview 09-2025
Input modalities
Claude Sonnet 4.5
Output modalities
Gemini 2.5 Flash Preview 09-2025
Output modalities

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
model details, providers and pricing
model details, providers and pricing
Claude Sonnet 4.5
Gemini 2.5 Flash Preview 09-2025