Llama 4 (405B) vs Llama 3.1 8B
Head-to-head technical comparison of intelligence, capabilities, and API pricing.
Llama 4 (405B)
Meta
AI Mastery Index90.5
LMSYS Arena1285
Technical (MMLU-Pro)90.5%
Cost per 1M Tokens$0
Llama 3.1 8B
Meta
AI Mastery Index75
LMSYS Arena1170
Technical (MMLU-Pro)73%
Cost per 1M Tokens$0
Architect's Verdict
When comparing Llama 4 (405B) and Llama 3.1 8B, Llama 4 (405B) edges out in overall capabilities according to the AI Mastery Index. However, for cost-sensitive workloads, Llama 3.1 8B 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.