Llama 3.1 405B vs Llama 4 Scout

Compare Llama 3.1 405B and Llama 4 Scout, both from Meta AI, context windows of 128K vs 10.0M, tested across 7 shared challenges. Updated April 2026.

Which is better, Llama 3.1 405B or Llama 4 Scout?

Llama 3.1 405B and Llama 4 Scout are both competitive models. Llama 3.1 405B costs $2.7/M input tokens vs $0.25/M for Llama 4 Scout. Context windows: 128K vs 10000K tokens. Compare their real outputs side by side below.

Key Differences Between Llama 3.1 405B and Llama 4 Scout

Llama 3.1 405B is made by meta while Llama 4 Scout is from meta. Llama 3.1 405B has a 128K token context window compared to Llama 4 Scout's 10000K. On pricing, Llama 3.1 405B costs $2.7/M input tokens vs $0.25/M for Llama 4 Scout.

Our Verdict
Llama 3.1 405B
Llama 3.1 405B
Llama 4 Scout
Llama 4 Scout

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

Llama 4 Scout is 6.2x cheaper per token — worth considering if cost matters.

Too close to call
Writing DNA

Style Comparison

Similarity
41%

Llama 4 Scout uses 412.3x more bold

Llama 3.1 405B
Llama 4 Scout
56%Vocabulary43%
15wSentence Length42w
0.41Hedging0.81
0.0Bold4.1
1.9Lists7.3
0.03Emoji0.00
0.00Headings0.30
0.16Transitions0.04
Based on 5 + 10 text responses
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Llama 3.1 405BLlama 4 Scout

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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