o3 vs Llama 3.1 405B
Pricing, context window, and benchmark comparison · Last updated April 2026
Llama 3.1 405B is cheaper than o3 at $2.70/1M/1M vs $10.00/1M/1M input tokens — a 3.7x cost difference. o3 scores higher on quality benchmarks (ELO 1380). Choose Llama 3.1 405B for cost-sensitive workloads; choose o3 for maximum quality.
Which is cheaper: o3 or Llama 3.1 405B?
Llama 3.1 405B is the cheaper option at $2.70/1M per 1M input tokens, compared to $10.00/1M for o3. That is a 3.7x cost difference on input tokens. Output pricing follows a similar pattern: o3 charges $40.00/1M/1M vs $2.70/1M/1M for Llama 3.1 405B.
Which has better quality: o3 or Llama 3.1 405B?
Based on LMSYS Chatbot Arena rankings, o3 achieves a higher ELO score (1380 vs 1267), suggesting stronger performance on open-ended tasks. o3 excels at highest reasoning benchmark scores of any model. Llama 3.1 405B is known for open source — can be self-hosted for data privacy.
Which should you choose: o3 or Llama 3.1 405B?
- → Highest reasoning benchmark scores of any model
- → Better cost-efficiency than o1 at similar quality
- → Superior at agentic and multi-step tasks
- → Open source — can be self-hosted for data privacy
- → Competitive with GPT-4o on many benchmarks
- → Strong multilingual capabilities
Frequently Asked Questions
Which is cheaper: o3 or Llama 3.1 405B?
Llama 3.1 405B is cheaper at $2.70/1M per 1M input tokens, making it 3.7x more affordable.
Which has better quality: o3 or Llama 3.1 405B?
o3 scores higher on the LMSYS Chatbot Arena with an ELO of 1380, suggesting better overall quality for most tasks.
Which has a larger context window: o3 or Llama 3.1 405B?
o3 has a larger context window at 200K tokens.
Should I choose o3 or Llama 3.1 405B?
Choose Llama 3.1 405B if cost is the priority. Choose o3 if benchmark quality is most important. Consider your specific use case: o3 is best for reasoning and math, while Llama 3.1 405B excels at coding and research.
Is o3 or Llama 3.1 405B open source?
o3 is proprietary. Llama 3.1 405B is open source.