Claude 3 Opus vs GPT-4o mini

Compare Claude 3 Opus by Anthropic against GPT-4o mini by OpenAI, context windows of 200K vs 128K, tested across 11 shared challenges. Updated April 2026.

Which is better, Claude 3 Opus or GPT-4o mini?

Claude 3 Opus and GPT-4o mini are both competitive models. Claude 3 Opus costs $15/M input tokens vs $0.15/M for GPT-4o mini. Context windows: 200K vs 128K tokens. Compare their real outputs side by side below.

Key Differences Between Claude 3 Opus and GPT-4o mini

Claude 3 Opus is made by anthropic while GPT-4o mini is from openai. Claude 3 Opus has a 200K token context window compared to GPT-4o mini's 128K. On pricing, Claude 3 Opus costs $15/M input tokens vs $0.15/M for GPT-4o mini.

Our Verdict
Claude 3 Opus
Claude 3 Opus
GPT-4o mini
GPT-4o miniRunner-up

No community votes yet. On paper, Claude 3 Opus has the edge — bigger model tier, bigger context window.

GPT-4o mini is 125x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
97%

GPT-4o mini uses 384.3x more bold

Claude 3 Opus
GPT-4o mini
54%Vocabulary54%
14wSentence Length18w
0.48Hedging0.84
0.0Bold3.8
3.0Lists3.3
0.00Emoji0.00
0.00Headings1.03
0.06Transitions0.23
Based on 3 + 22 text responses
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Claude 3 OpusGPT-4o mini

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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