Gemini 3.1 Pro Preview is cheaper than GPT-5 Pro at $2/M vs $15/M input tokens.
| Spec | Gemini 3.1 Pro Preview | GPT-5 Pro |
|---|---|---|
| Input price | $2/M tokens | $15/M tokens |
| Output price | $12/M tokens | $120/M tokens |
| Context window | 1.0M tokens | 400K tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Feb 2026 | Oct 2025 |
| SWE-bench Verified | 80.6% | 74.9% |
Not enough votes to call it. On the specs, Gemini 3.1 Pro Preview has the edge: newer, bigger context window.
Gemini 3.1 Pro Preview costs 10x less per token.
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Gemini 3.1 Pro Preview is cheaper on both: 7.5× input, 10× output.
Per million tokens. Prices and uptime via OpenRouter, checked 13 Sep 2026.
Gemini 3.1 Pro Preview uses 487.7x more bold