# Gemini 3 Deep Think vs GPT-5.5 Pro

> GPT-5.5 Pro has enough public results to be ranked (#8); Gemini 3 Deep Think does not yet, so treat this comparison as directional.

- Canonical page: https://noometry.com/compare/gemini-3-deep-think-vs-gpt-5-5-pro
- Last updated: 2026-10-12
- Shared benchmarks: 3

## Summary

- They share 3 benchmarks with published results for both. Gemini 3 Deep Think scores higher in 0 categories and GPT-5.5 Pro in 1 category; one gap is clear of the uncertainty.
- The widest gap is in reasoning, where GPT-5.5 Pro leads 73.3 to 70.2.

## Snapshot

| | Gemini 3 Deep Think | GPT-5.5 Pro |
|---|---|---|
| Provider | Google | OpenAI |
| Noometry Index | 58.3 | 64.3 |
| Rank | — | 8 |
| Context | — | 1.05M |
| Input $/M | — | $30 |
| Output $/M | — | $180 |
| Weights | Proprietary | Proprietary |

## Reasoning

- Gemini 3 Deep Think: 70.2 (#14)
- GPT-5.5 Pro: 73.3 (#10)

| Benchmark | Gemini 3 Deep Think | GPT-5.5 Pro |
|---|---|---|
| ARC-AGI-2 | 84.6% | 84.6% |
| ARC-AGI-1 | 96% | 96.5% |
| CritPt | 25.7% | 30.6% |
| SimpleBench | — | 76.9% |
| Chess Puzzles | — | 64% |
| DTBench | — | 96% |
| LMCA | — | 53.9% |
| Epoch Capabilities Index | — | 162.07 |

## Math

- Gemini 3 Deep Think: —
- GPT-5.5 Pro: 84.0 (#10)

| Benchmark | Gemini 3 Deep Think | GPT-5.5 Pro |
|---|---|---|
| FrontierMath (Tiers 1-3) | — | 87.7% |
| FrontierMath Tier 4 | — | 78% |
| OTIS Mock AIME 2024-2025 | — | 100% |
| FrontierMath (Feb 2025 set) | — | 52.4% |
| FrontierMath Tier 4 (v1) | — | 39.6% |

## Knowledge

- Gemini 3 Deep Think: —
- GPT-5.5 Pro: 64.1 (#19)

| Benchmark | Gemini 3 Deep Think | GPT-5.5 Pro |
|---|---|---|
| GPQA Diamond | — | 93.9% |

## FAQ

### Is Gemini 3 Deep Think better than GPT-5.5 Pro?

GPT-5.5 Pro has enough public results to be ranked (#8); Gemini 3 Deep Think does not yet, so treat this comparison as directional.

### How many benchmarks do Gemini 3 Deep Think and GPT-5.5 Pro share?

3 benchmarks have published results for both models. Gemini 3 Deep Think has 3 scored results on Noometry and GPT-5.5 Pro has 14.