Claude 3 Opus vs Claude Sonnet 4

Compare Claude 3 Opus and Claude Sonnet 4, both from Anthropic, context windows of 200K vs 200K, tested across 9 shared challenges. Updated April 2026.

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

Claude 3 Opus and Claude Sonnet 4 are both competitive models. Claude 3 Opus costs $15/M input tokens vs $3/M for Claude Sonnet 4. Context windows: 200K vs 200K tokens. Compare their real outputs side by side below.

Key Differences Between Claude 3 Opus and Claude Sonnet 4

Claude 3 Opus is made by anthropic while Claude Sonnet 4 is from anthropic. Claude 3 Opus has a 200K token context window compared to Claude Sonnet 4's 200K. On pricing, Claude 3 Opus costs $15/M input tokens vs $3/M for Claude Sonnet 4.

Our Verdict
Claude 3 Opus
Claude 3 Opus
Claude Sonnet 4
Claude Sonnet 4

No community votes yet. On paper, these are closely matched - try both with your actual task to see which fits your workflow.

Claude Sonnet 4 is 5.0x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
84%

Claude Sonnet 4 uses 503.7x more bold

Claude 3 Opus
Claude Sonnet 4
54%Vocabulary62%
14wSentence Length111w
0.48Hedging0.40
0.0Bold5.0
3.0Lists9.3
0.00Emoji0.88
0.00Headings2.16
0.06Transitions0.33
Based on 3 + 17 text responses
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Claude 3 OpusClaude Sonnet 4

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

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