o1-preview vs Gemini 3.1 Ultra

Head-to-head technical comparison of intelligence, capabilities, and API pricing.

o1-preview

OpenAI

AI Mastery Index88.5

LMSYS Arena1335

Technical (MMLU-Pro)90.8%

Cost per 1M Tokens$15

Gemini 3.1 Ultra

Google

AI Mastery Index92.5

LMSYS Arena1320

Technical (MMLU-Pro)92.5%

Cost per 1M Tokens$20

Architect's Verdict

When comparing o1-preview and Gemini 3.1 Ultra, Gemini 3.1 Ultra edges out in overall capabilities according to the AI Mastery Index. However, for cost-sensitive workloads, o1-preview offers a more economical API at $15 per 1M tokens. Your choice should depend heavily on whether you prioritize raw reasoning (MMLU) or scalable deployment economics.