GPT-5.1
Nothing here. The model returned empty. We stared at it for a while.
GPT-5.1 vs xAI: Grok 4
Compare GPT-5.1 by OpenAI against xAI: Grok 4 by xAI, context windows of 400K vs 256K, tested across 37 shared challenges. Updated April 2026.
Which is better, GPT-5.1 or xAI: Grok 4?
GPT-5.1 and xAI: Grok 4 are both competitive models. GPT-5.1 costs $1.25/M input tokens vs $3/M for xAI: Grok 4. Context windows: 400K vs 256K tokens. Compare their real outputs side by side below.
Key Differences Between GPT-5.1 and xAI: Grok 4
GPT-5.1 is made by openai while xAI: Grok 4 is from xai. GPT-5.1 has a 400K token context window compared to xAI: Grok 4's 256K. On pricing, GPT-5.1 costs $1.25/M input tokens vs $3/M for xAI: Grok 4.
Our Verdict
GPT-5.1
xAI: Grok 4Runner-up
No community votes yet. On paper, GPT-5.1 has the edge — bigger model tier, newer, bigger context window.
Slight edge
Writing DNA
Style Comparison
Similarity
98%
xAI: Grok 4 uses 7.0x more emoji
GPT-5.1
xAI: Grok 4
62%Vocabulary53%
19wSentence Length18w
0.29Hedging0.67
3.5Bold2.7
7.2Lists2.7
0.00Emoji0.07
0.61Headings0.86
0.03Transitions0.04
Based on 14 + 21 text responses
vs
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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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