GPT-4o Mini vs Llama 3.1 405B: Detailed Comparison

Choosing between GPT-4o Mini (OpenAI) and Llama 3.1 405B (Meta) comes down to three things: per-token pricing, context window, and which capability matters most for your workload. GPT-4o Mini costs $0.15/M input vs $3.50/M for Llama 3.1 405B; context windows are 128K vs 128K tokens. Detailed breakdown below.

Side-by-side specs

SpecGPT-4o MiniLlama 3.1 405B
ProviderOpenAIMeta
Released2024-07-182024-07-23
Input price $0.15/M $3.50/M
Output price $0.60/M $3.50/M
Cached input $0.0750/M
Context window 128K 128K
Max output 16K 4K
Modalities text image text
Tokenizer o200k_base llama-3

Capability matrix

CapabilityGPT-4o MiniLlama 3.1 405B
function calling Yes Yes
json mode Yes Yes
vision Yes No
streaming Yes Yes

Per-call cost on typical workloads

Workload (in/out tokens)GPT-4o MiniLlama 3.1 405BCheaper by
Standard chat (1K / 500) $0.000450 $0.005250 GPT-4o Mini by $0.004800
RAG (4K / 500) $0.000900 $0.015750 GPT-4o Mini by $0.014850
Long doc (20K / 1K) $0.003600 $0.073500 GPT-4o Mini by $0.069900
Very long context (100K / 2K) $0.015900 $0.355250 GPT-4o Mini by $0.339350

When to choose GPT-4o Mini over Llama 3.1 405B

  • Per-token input cost is 96% lower — meaningful for high-volume workloads.
  • Supports vision — Llama 3.1 405B does not.

When to choose Llama 3.1 405B over GPT-4o Mini

  • Llama 3.1 405B fits when your stack is already on Meta.

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