Claude 3 Opus vs Claude Sonnet 4.5

Compare Claude 3 Opus and Claude Sonnet 4.5, both from Anthropic, in 2 community votes, claude 3 opus and claude sonnet 4.5 are closely matched, context windows of 200K vs 200K, tested across 12 shared challenges. Updated April 2026.

Which is better, Claude 3 Opus or Claude Sonnet 4.5?

Claude 3 Opus and Claude Sonnet 4.5 are closely matched based on 2 community votes. Claude 3 Opus costs $15/M input tokens vs $3/M for Claude Sonnet 4.5. Context windows: 200K vs 200K tokens. Compare their real outputs side by side below.

Key Differences Between Claude 3 Opus and Claude Sonnet 4.5

Claude 3 Opus is made by anthropic while Claude Sonnet 4.5 is from anthropic. Claude 3 Opus has a 200K token context window compared to Claude Sonnet 4.5's 200K. On pricing, Claude 3 Opus costs $15/M input tokens vs $3/M for Claude Sonnet 4.5. In community voting, In 2 community votes, Claude 3 Opus and Claude Sonnet 4.5 are closely matched.

In 2 community votes, Claude 3 Opus and Claude Sonnet 4.5 are closely matched. Based on blind community voting from the Rival open dataset of 2+ human preference judgments for this pair.

Our Verdict
Claude Sonnet 4.5
Claude Sonnet 4.5Winner
Claude 3 Opus
Claude 3 OpusRunner-up

Votes are tied. Claude Sonnet 4.5 is newer and likely incorporates more recent improvements.

Claude Sonnet 4.5 is 5.0x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
84%

Claude Sonnet 4.5 uses 490.1x more bold

Claude 3 Opus
Claude Sonnet 4.5
54%Vocabulary64%
14wSentence Length94w
0.48Hedging0.48
0.0Bold4.9
3.0Lists8.0
0.00Emoji0.45
0.00Headings1.91
0.06Transitions0.07
Based on 3 + 20 text responses
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Claude 3 OpusClaude Sonnet 4.5

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