GPT-5 Nano vs Grok 3

Compare GPT-5 Nano by OpenAI against Grok 3 by xAI, tested across 45 shared challenges. Updated April 2026.

Which is better, GPT-5 Nano or Grok 3?

GPT-5 Nano and Grok 3 are both competitive models. Compare their real outputs side by side below.

Key Differences Between GPT-5 Nano and Grok 3

GPT-5 Nano is made by openai while Grok 3 is from xai.

Our Verdict
GPT-5 Nano
GPT-5 Nano
Grok 3
Grok 3

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

Too close to call
Writing DNA

Style Comparison

Similarity
81%

Grok 3 uses 246.4x more bold

GPT-5 Nano
Grok 3
59%Vocabulary49%
25wSentence Length18w
0.23Hedging0.94
0.0Bold2.5
4.2Lists3.0
0.00Emoji0.04
0.00Headings0.65
0.01Transitions0.08
Based on 14 + 17 text responses
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GPT-5 NanoGrok 3

279 AI models invented the same fake scientist.

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

AI Hallucination Index 2026
Free preview13 of 58 slides
FAQ

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