# Gemma 3 12B vs o3-pro

> o3-pro is the stronger model overall, scoring 42.9 to 32.1 on the Noometry Index. Gemma 3 12B costs 467× less per token, which makes it the better buy when o3-pro's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gemma-3-12b-vs-o3-pro
- Last updated: 2026-10-10
- Shared benchmarks: 4

## Summary

- They share 4 benchmarks with published results for both. Gemma 3 12B scores higher in 0 categories and o3-pro in 5 categories; 5 gaps are clear of the uncertainty.
- The widest gap is in long context, where o3-pro leads 72.2 to 40.0.
- The biggest single-benchmark swing is DTBench: 48.8% for Gemma 3 12B and 86.9% for o3-pro.
- Gemma 3 12B is cheaper at $0.05 / $0.15 per million input/output tokens, against $20 / $80 for o3-pro.
- o3-pro accepts more context: 200K tokens versus 131K.
- Gemma 3 12B has downloadable open weights; the other is API-only.

## Snapshot

| | Gemma 3 12B | o3-pro |
|---|---|---|
| Provider | Google | OpenAI |
| Noometry Index | 32.1 | 42.9 |
| Rank | 262 | 105 |
| Context | 131K | 200K |
| Input $/M | $0.05 | $20 |
| Output $/M | $0.15 | $80 |
| Weights | Open | Proprietary |

## Coding

- Gemma 3 12B: 31.7 (#280)
- o3-pro: 55.5 (#24)

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| Aider Polyglot | — | 84.9% |
| SciCode | 17.4% | — |
| WeirdML | — | 58.2% |
| LMArena Coding | 1281 | — |

## Agentic & Tool Use

- Gemma 3 12B: 25.5 (#108)
- o3-pro: —

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| Berkeley Function Calling Leaderboard | 30.4% | — |

## Reasoning

- Gemma 3 12B: 15.7 (#313)
- o3-pro: 23.8 (#171)

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| DTBench | 48.8% | 86.9% |
| LMCA | 4.5% | 38.5% |
| Epoch Capabilities Index | 123.5 | 147.42 |
| ARC-AGI-2 | — | 4.9% |
| Kagi LLM Benchmark | — | 72.1% |
| ARC-AGI-1 | — | 59.3% |
| CritPt | 0% | — |
| Chess Puzzles | 0% | — |
| LMArena Hard Prompts | 1309 | — |

## Math

- Gemma 3 12B: 22.3 (#279)
- o3-pro: —

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 16.7% | — |
| LMArena Math | 1307 | — |

## Knowledge

- Gemma 3 12B: 26.5 (#257)
- o3-pro: 29.5 (#238)

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| Vectara Hallucination Rate | 4.4% | 23.3% |
| GPQA Diamond | 39.5% | — |
| Confabulations | — | 14.2% |
| LMArena Expert | 1248 | — |

## Multimodal

- Gemma 3 12B: —
- o3-pro: —

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| MindCube | 46.7% | — |

## Multilingual

- Gemma 3 12B: 45.7 (#165)
- o3-pro: —

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| LMArena Non-English | 1318 | — |
| LMArena German | 1370 | — |
| LMArena Russian | 1335 | — |

## Instruction Following

- Gemma 3 12B: 68.6 (#186)
- o3-pro: —

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| LMArena Instruction Following | 1299 | — |

## Long Context

- Gemma 3 12B: 40.0 (#162)
- o3-pro: 72.2 (#1)

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| Fiction.LiveBench | — | 97.2% |
| LMArena Longer Query | 1317 | — |

## Writing & Preference

- Gemma 3 12B: 47.5 (#209)
- o3-pro: 57.1 (#133)

| Benchmark | Gemma 3 12B | o3-pro |
|---|---|---|
| LMArena Text | 1334 | — |
| LMArena Creative Writing | 1331 | — |
| Short-Story Creative Writing | — | 84.4% |
| EQ-Bench Creative Writing | 1126 | — |
| LMArena Multi-Turn | 1334 | — |

## FAQ

### Is Gemma 3 12B better than o3-pro?

o3-pro is the stronger model overall, scoring 42.9 to 32.1 on the Noometry Index. Gemma 3 12B costs 467× less per token, which makes it the better buy when o3-pro's lead doesn't matter for your workload.

### Which is cheaper, Gemma 3 12B or o3-pro?

Gemma 3 12B is cheaper. It lists at $0.05 per million input tokens and $0.15 per million output tokens; o3-pro lists at $20 and $80.

### Is Gemma 3 12B or o3-pro better for coding?

o3-pro scores higher on coding benchmarks: 55.5 versus 31.7 in the Noometry coding category.

### Which has the bigger context window?

o3-pro does, with 200K tokens against 131K.

### How many benchmarks do Gemma 3 12B and o3-pro share?

4 benchmarks have published results for both models. Gemma 3 12B has 24 scored results on Noometry and o3-pro has 12.