# Gemini 2.5 Flash vs o3-mini

> Gemini 2.5 Flash is the stronger model overall, scoring 39.3 to 36.7 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gemini-2-5-flash-vs-o3-mini
- Last updated: 2026-10-11
- Shared benchmarks: 33

## Summary

- They share 33 benchmarks with published results for both. Gemini 2.5 Flash scores higher in 7 categories and o3-mini in 2 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in long context, where Gemini 2.5 Flash leads 47.5 to 33.8.
- The biggest single-benchmark swing is Fiction.LiveBench: 77.8% for Gemini 2.5 Flash and 50% for o3-mini.
- Gemini 2.5 Flash is cheaper at $0.30 / $2.50 per million input/output tokens, against $1.10 / $4.40 for o3-mini.
- Gemini 2.5 Flash accepts more context: 1.05M tokens versus 200K.

## Snapshot

| | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| Provider | Google | OpenAI |
| Noometry Index | 39.3 | 36.7 |
| Rank | 170 | 212 |
| Context | 1.05M | 200K |
| Input $/M | $0.30 | $1.10 |
| Output $/M | $2.50 | $4.40 |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 2.5 Flash: 35.8 (#220)
- o3-mini: 40.8 (#132)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| Aider Polyglot | 55.1% | 60.4% |
| WeirdML | 41.9% | 43.7% |
| LMArena Coding | 1424 | 1378 |
| SWE-bench Verified (bash only) | 28.7% | — |
| SciCode | — | 39.8% |
| GSO | — | 1.3% |
| LiveBench Coding | — | 82.7% |
| CadEval | — | 54% |
| ALE-Bench | 661.88 | — |

## Agentic & Tool Use

- Gemini 2.5 Flash: 30.8 (#74)
- o3-mini: 29.6 (#84)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| Terminal-Bench | 17.1% | — |
| Berkeley Function Calling Leaderboard | 56.2% | — |
| TheAgentCompany | 41.1% | — |
| Cybench | — | 22.5% |
| BALROG | 33.5% | — |
| Vending-Bench 2 | 548.84 | — |

## Reasoning

- Gemini 2.5 Flash: 18.1 (#286)
- o3-mini: 16.3 (#305)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| ARC-AGI-2 | 2.5% | 3% |
| SimpleBench | 41.2% | 22.8% |
| ARC-AGI-1 | 33.3% | 34.5% |
| CritPt | 1.1% | 0.3% |
| LMArena Hard Prompts | 1422 | 1366 |
| DTBench | 76.5% | 68.8% |
| LMCA | 27.5% | 19% |
| Epoch Capabilities Index | 143.03 | 140.34 |
| ForecastBench | 60.6 | 59.6 |
| Kagi LLM Benchmark | 56.8% | — |
| Chess Puzzles | — | 17% |
| EnigmaEval | 2.7% | — |
| LiveBench Reasoning | — | 89.6% |
| Mystery Game Puzzles | — | 7% |
| LiveBench Data Analysis | — | 70.6% |
| LiveBench | — | 75.9% |

## Math

- Gemini 2.5 Flash: 39.9 (#98)
- o3-mini: 28.1 (#244)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 73.1% | 76.9% |
| LMArena Math | 1415 | 1396 |
| FrontierMath (Feb 2025 set) | 4.8% | 12.4% |
| FrontierMath Tier 4 (v1) | 4.2% | 4.2% |
| FrontierMath (Tiers 1-3) | — | 18.6% |
| FrontierMath Tier 4 | — | 0% |
| Omni-MATH | 38.5% | — |
| LiveBench Math | — | 77.3% |
| MATH Level 5 | — | 96.5% |

## Knowledge

- Gemini 2.5 Flash: 36.4 (#168)
- o3-mini: 38.3 (#146)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| Confabulations | 16.8% | 17.9% |
| LMArena Expert | 1426 | 1364 |
| GPQA Diamond | — | 77% |
| Humanity's Last Exam | 12.1% | — |
| SimpleQA Verified | — | 15.3% |
| MMLU-Pro | 63.9% | — |
| Vectara Hallucination Rate | 7.8% | — |
| GPQA (HELM) | 39% | — |

## Multimodal

- Gemini 2.5 Flash: 41.8 (#32)
- o3-mini: —

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| LMArena Vision | 1253 | — |
| GeoBench | 76% | — |
| VPCT | 46.2% | — |
| SpatialViz-Bench | 36.9% | — |

## Multilingual

- Gemini 2.5 Flash: 52.3 (#88)
- o3-mini: 45.7 (#164)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| LMArena Non-English | 1409 | 1319 |
| LMArena Chinese | 1450 | 1379 |
| LMArena French | 1433 | 1334 |
| LMArena German | 1418 | 1303 |
| LMArena Japanese | 1405 | 1286 |
| LMArena Korean | 1385 | 1314 |
| LMArena Russian | 1415 | 1304 |
| LMArena Spanish | 1421 | 1321 |

## Instruction Following

- Gemini 2.5 Flash: 75.7 (#54)
- o3-mini: 75.1 (#72)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| LMArena Instruction Following | 1405 | 1337 |
| LiveBench Instruction Following | — | 84.4% |
| IFEval | 89.8% | — |

## Long Context

- Gemini 2.5 Flash: 47.5 (#17)
- o3-mini: 33.8 (#256)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| Fiction.LiveBench | 77.8% | 50% |
| LMArena Longer Query | 1419 | 1343 |

## Writing & Preference

- Gemini 2.5 Flash: 53.8 (#157)
- o3-mini: 50.3 (#182)

| Benchmark | Gemini 2.5 Flash | o3-mini |
|---|---|---|
| LMArena Text | 1417 | 1337 |
| LMArena Creative Writing | 1400 | 1286 |
| Short-Story Creative Writing | 76.5% | 61.7% |
| LMArena Multi-Turn | 1408 | 1320 |
| EQ-Bench Creative Writing | 1137 | — |
| WildBench | 81.7% | — |
| LiveBench Language | — | 50.7% |

## FAQ

### Is Gemini 2.5 Flash better than o3-mini?

Gemini 2.5 Flash is the stronger model overall, scoring 39.3 to 36.7 on the Noometry Index.

### Which is cheaper, Gemini 2.5 Flash or o3-mini?

Gemini 2.5 Flash is cheaper. It lists at $0.30 per million input tokens and $2.50 per million output tokens; o3-mini lists at $1.10 and $4.40.

### Is Gemini 2.5 Flash or o3-mini better for coding?

o3-mini scores higher on coding benchmarks: 40.8 versus 35.8 in the Noometry coding category.

### Which has the bigger context window?

Gemini 2.5 Flash does, with 1.05M tokens against 200K.

### How many benchmarks do Gemini 2.5 Flash and o3-mini share?

33 benchmarks have published results for both models. Gemini 2.5 Flash has 54 scored results on Noometry and o3-mini has 51.