GPT-5 Mini vs Llama 3.1 405B
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for GPT-5 Mini and Llama 3.1 405B.
GPT-5 Mini
GPT-5 Mini is a compact version of GPT-5, designed to handle lighter-weight reasoning tasks. It provides the same instruction-following and safety-tuning benefits as GPT-5, but with reduced latency and cost....
Llama 3.1 405B
Llama 3.1 405B is Meta's largest open-weight language model and one of the most capable openly available models in the world. With 405 billion parameters, it achieves performance competitive with GPT-4 and Claude Opus across benchmarks spanning general knowledge, mathematics, coding, and multilingual tasks. Llama 3.1 405B is released under Meta's custom commercial license, supporting broad use cases including deployment via major cloud providers (AWS, GCP, Azure) and self-hosted inference with multi-GPU configurations.
Technical Specifications
| Specification | GPT-5 Mini | Llama 3.1 405B |
|---|---|---|
| Provider | OpenAI | Meta |
| Context Window | 400,000 tokens | 131,072 tokens |
| Agent Suitability | 85/100 | 90/100 |
| Time to First Token (TTFT) | 180 ms | 550 ms |
| Deployment Model | managed api | self hostable |
| Production Stability | stable | stable |
| API Available | Yes | Yes |
| Released Date | 2025-08-07 | 2024-07-23 |
API Pricing Comparison
Input Price per Million Tokens
GPT-5 Mini
$0.25
Llama 3.1 405B
$0.80
Output Price per Million Tokens
GPT-5 Mini
$2.00
Llama 3.1 405B
$0.80
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
GPT-5 Mini Quirks & Gotchas
- ▸Excellent for high-frequency classification and routing tasks
- ▸Tool calling reliability drops on complex multi-step chains — use GPT-5 for agentic workflows
Llama 3.1 405B Quirks & Gotchas
- ▸Massive model — requires 8× A100 80GB for FP16 inference
- ▸Available via Together AI, Fireworks, and Bedrock as managed API