Claude 3 Sonnet vs Claude Opus 4

Compare Claude 3 Sonnet and Claude Opus 4, both from Anthropic, tested across 8 shared challenges. Updated April 2026.

Which is better, Claude 3 Sonnet or Claude Opus 4?

Claude 3 Sonnet and Claude Opus 4 are both competitive models. Claude 3 Sonnet costs $3/M input tokens vs $15/M for Claude Opus 4. Compare their real outputs side by side below.

Key Differences Between Claude 3 Sonnet and Claude Opus 4

Claude 3 Sonnet is made by anthropic while Claude Opus 4 is from anthropic. On pricing, Claude 3 Sonnet costs $3/M input tokens vs $15/M for Claude Opus 4.

Our Verdict
Claude Opus 4
Claude Opus 4
Claude 3 Sonnet
Claude 3 SonnetRunner-up

No community votes yet. On paper, Claude Opus 4 has the edge — bigger model tier, newer, bigger context window.

Claude 3 Sonnet is 5.0x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
96%

Claude Opus 4 uses 444.0x more bold

Claude 3 Sonnet
Claude Opus 4
48%Vocabulary64%
14wSentence Length62w
0.32Hedging0.52
0.0Bold4.4
3.6Lists9.1
0.00Emoji0.11
0.00Headings1.87
0.38Transitions0.27
Based on 4 + 16 text responses
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Claude 3 SonnetClaude Opus 4

279 AI models invented the same fake scientist.

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AI Hallucination Index 2026
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