What is the difference between Claude Sonnet 4.5 and Gemini 2.5 Flash Preview 05-20?

Claude Sonnet 4.5 is developed by Anthropic while Gemini 2.5 Flash Preview 05-20 is developed by Google AI. Claude Sonnet 4.5 has a 200K token context window vs Gemini 2.5 Flash Preview 05-20's 1.0M. You can compare their actual outputs across 10 challenges on Rival to see how they differ in practice.

Which is better, Claude Sonnet 4.5 or Gemini 2.5 Flash Preview 05-20?

It depends on your use case. Claude Sonnet 4.5 and Gemini 2.5 Flash Preview 05-20 each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 10 challenges so you can judge which fits your needs best.

How much does Claude Sonnet 4.5 cost compared to Gemini 2.5 Flash Preview 05-20?

Claude Sonnet 4.5 costs $3/M input tokens and Gemini 2.5 Flash Preview 05-20 costs $0.15/M input tokens. Gemini 2.5 Flash Preview 05-20 is $2.85/M cheaper per input. Check their side-by-side outputs on Rival to see if the price difference is justified by quality.

How can I compare Claude Sonnet 4.5 and Gemini 2.5 Flash Preview 05-20 on Rival?

This page shows a side-by-side comparison of Claude Sonnet 4.5 and Gemini 2.5 Flash Preview 05-20 across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Updated Sep 2025

Claude Sonnet 4.5vsGemini 2.5 Flash Preview 05-20

Gemini 2.5 Flash Preview 05-20 is cheaper than Claude Sonnet 4.5 at $0.15/M vs $3/M input tokens.

Claude Sonnet 4.5 and Gemini 2.5 Flash Preview 05-20 compared across 10 shared prompts
Spec	Claude Sonnet 4.5	Gemini 2.5 Flash Preview 05-20
Input price	$3/M tokens	$0.15/M tokens
Output price	$15/M tokens	$0.6/M tokens
Context window	200K tokens	1.0M tokens
Weights	Closed	—
Free API (OpenRouter)	No	No
Released	Sep 2025	May 2025