GPT-5.5 vs Gemini 3.1 Pro: Performance, Cost, and Privacy Compared
对比评测2026-05-241 min read

GPT-5.5 vs Gemini 3.1 Pro: Performance, Cost, and Privacy Compared

Comprehensive comparison of OpenAI GPT-5.5 vs Google Gemini 3.1 Pro. Benchmarks, coding, context windows, API costs, and privacy policies analyzed side by side.

Contents

English Version

Executive Summary

As LLM technology rapidly evolves, OpenAI and Google have released their latest flagship models — GPT-5.5 (powering ChatGPT) and Gemini 3.1 Pro. Both represent the cutting edge in general intelligence and multimodal reasoning.

Key Findings

Gemini 3.1 Pro leads in knowledge and reasoning: 92.6% on MMLU vs GPT-4's 86.4%. GPT-5.5 excels at coding: 82.7% on Terminal-Bench 2.0.

Cost difference is massive: Gemini costs ~1/15 of GPT-5.5. Input $2 vs $30 per 1M tokens.

Privacy: Google does NOT train on user data. OpenAI does by default (can opt out).

Recommendation

  • Best chat experience + ecosystem → ChatGPT/GPT-5.5
  • Best reasoning + multimodal + budget → Gemini 3.1 Pro
  • Privacy-sensitive enterprise → Gemini
  • Large-scale deployment → Gemini (15x cheaper)