Claude 3 Opus vs Llama 3.1 405B

Compare Claude 3 Opus by Anthropic against Llama 3.1 405B by Meta AI, context windows of 200K vs 128K, tested across 7 shared challenges. Updated March 2026.

Which is better, Claude 3 Opus or Llama 3.1 405B?

Claude 3 Opus and Llama 3.1 405B are both competitive models. Claude 3 Opus costs $15/M input tokens vs $2.7/M for Llama 3.1 405B. Context windows: 200K vs 128K tokens. Compare their real outputs side by side below.

Key Differences Between Claude 3 Opus and Llama 3.1 405B

Claude 3 Opus is made by anthropic while Llama 3.1 405B is from meta. Claude 3 Opus has a 200K token context window compared to Llama 3.1 405B's 128K. On pricing, Claude 3 Opus costs $15/M input tokens vs $2.7/M for Llama 3.1 405B.

Our Verdict
Claude 3 Opus
Claude 3 Opus
Llama 3.1 405B
Llama 3.1 405B

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

Llama 3.1 405B is 24x cheaper per token — worth considering if cost matters.

Too close to call
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Claude 3 OpusLlama 3.1 405B
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