Claude 3 Opus vs Gemini 2.5 Flash Preview (thinking)

Compare Claude 3 Opus by Anthropic against Gemini 2.5 Flash Preview (thinking) by Google AI, in 1 community votes, claude 3 opus wins 100% of head-to-head duels, context windows of 200K vs 1.0M, tested across 9 shared challenges. Updated March 2026.

Which is better, Claude 3 Opus or Gemini 2.5 Flash Preview (thinking)?

Claude 3 Opus is the better choice overall, winning 100% of 1 blind community votes on Rival. Claude 3 Opus costs $15/M input tokens vs $0.175/M for Gemini 2.5 Flash Preview (thinking). Context windows: 200K vs 1049K tokens. Compare their real outputs side by side below.

Key Differences Between Claude 3 Opus and Gemini 2.5 Flash Preview (thinking)

Claude 3 Opus is made by anthropic while Gemini 2.5 Flash Preview (thinking) is from google. Claude 3 Opus has a 200K token context window compared to Gemini 2.5 Flash Preview (thinking)'s 1049K. On pricing, Claude 3 Opus costs $15/M input tokens vs $0.175/M for Gemini 2.5 Flash Preview (thinking). In community voting, In 1 community votes, Claude 3 Opus wins 100% of head-to-head duels.

In 1 community votes, Claude 3 Opus wins 100% of head-to-head duels. Based on blind community voting from the Rival open dataset of 1+ human preference judgments for this pair.

Our Verdict
Claude 3 Opus
Claude 3 OpusWinner
Gemini 2.5 Flash Preview (thinking)
Gemini 2.5 Flash Preview (thinking)Runner-up

Pick Claude 3 Opus. In 1 blind votes, Claude 3 Opus wins 100% of the time. That's not luck.

Gemini 2.5 Flash Preview (thinking) is 21x cheaper per token — worth considering if cost matters.

Clear winner
vs

Ask them anything yourself

Claude 3 OpusGemini 2.5 Flash Preview (thinking)
FAQ