GPT-5.1 vs Mistral Medium 3

Compare GPT-5.1 by OpenAI against Mistral Medium 3 by Mistral AI, context windows of 400K vs 131K, tested across 27 shared challenges. Updated April 2026.

Which is better, GPT-5.1 or Mistral Medium 3?

GPT-5.1 and Mistral Medium 3 are both competitive models. GPT-5.1 costs $1.25/M input tokens vs $0.4/M for Mistral Medium 3. Context windows: 400K vs 131K tokens. Compare their real outputs side by side below.

Key Differences Between GPT-5.1 and Mistral Medium 3

GPT-5.1 is made by openai while Mistral Medium 3 is from mistral. GPT-5.1 has a 400K token context window compared to Mistral Medium 3's 131K. On pricing, GPT-5.1 costs $1.25/M input tokens vs $0.4/M for Mistral Medium 3.

Our Verdict
GPT-5.1
GPT-5.1
Mistral Medium 3
Mistral Medium 3Runner-up

No community votes yet. On paper, GPT-5.1 has the edge — bigger model tier, newer, bigger context window, major provider backing.

Mistral Medium 3 is 5.0x cheaper per token — worth considering if cost matters.

Slight edge
Writing DNA

Style Comparison

Similarity
98%

Mistral Medium 3 uses 6.0x more emoji

GPT-5.1
Mistral Medium 3
62%Vocabulary57%
19wSentence Length17w
0.29Hedging0.73
3.5Bold8.6
7.2Lists6.5
0.00Emoji0.06
0.61Headings1.18
0.03Transitions0.15
Based on 14 + 15 text responses
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GPT-5.1Mistral Medium 3

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