Llama 3.1 405B vs Grok 4.5
Head-to-head technical comparison of intelligence, capabilities, and API pricing.
Llama 3.1 405B
Meta
AI Mastery Index85
LMSYS Arena1255
Technical (MMLU-Pro)88.6%
Cost per 1M Tokens$0
Grok 4.5
xAI
AI Mastery Index93.4
LMSYS Arena1465
Technical (MMLU-Pro)92.8%
Cost per 1M Tokens$2
Architect's Verdict
When comparing Llama 3.1 405B and Grok 4.5, Grok 4.5 edges out in overall capabilities according to the AI Mastery Index. However, for cost-sensitive workloads, Llama 3.1 405B offers a more economical API at $0 per 1M tokens. Your choice should depend heavily on whether you prioritize raw reasoning (MMLU) or scalable deployment economics.