Gemini 3.1 Pro Preview vs GPT-5.5
Side-by-side comparison across metrics, pricing, and overall score — every value traced to a source.
Verdict: GPT-5.5 ranks highest overall (#3) with a score of 52.5.
The best choice still depends on which metrics matter for your workload — per-metric winners are marked below.
What the numbers hide
Computed from the published values below — no estimates, no generated claims.
Fragile verdict
The overall winner flips to Gemini 3.1 Pro Preview if SWE-Bench Pro Score is weighted at 25% (it counts for 29% today). If swe-bench pro score drives your decision, the ranking above may not be your ranking.
Fragile verdict
The overall winner flips to Gemini 3.1 Pro Preview if Input Price is weighted at 30% (it counts for 24% today). If input price drives your decision, the ranking above may not be your ranking.
Real tradeoff
Gemini 3.1 Pro Preview clearly beats GPT-5.5 on Input Price but clearly loses on Context Window — this pair is a priorities question, not a quality question.
AI hot take
Sign in to generate a contrarian AI read of this comparison.
| Metric | Gemini 3.1 Pro PreviewGoogle | GPT-5.5OpenAI |
|---|---|---|
| Overall OptiSift Score | 50.8#5 | 52.5#3 |
| Input Price | $2 | $5 |
| Output Price | $12 | $30 |
| Cache Read Price | $0.2 | $0.5 |
| Context Window | 1.0M | 1.1M |
| Max Output Tokens | 66K | 128K |
| SWE-Bench Pro Score | 54.2% | 58.6% |
| Tool Calling | Yes | Yes |
| Extended Reasoning | Yes | Yes |
About these models
#5Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview is Google's reasoning-capable model: $2/$12 per 1M input/output tokens, 1.0M token context window, 54.2% on SWE-Bench Pro.
#3GPT-5.5
OpenAI
GPT-5.5 is OpenAI's reasoning-capable model: $5/$30 per 1M input/output tokens, 1.1M token context window, 58.6% on SWE-Bench Pro.