# Gemini 2.5 Flash-Lite vs o3

> o3 is the stronger model overall, scoring 47.5 to 37.0 on the Noometry Index. Gemini 2.5 Flash-Lite costs 20× less per token, which makes it the better buy when o3's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/gemini-2-5-flash-lite-vs-o3
- Last updated: 2026-10-11
- Shared benchmarks: 32

## Summary

- They share 32 benchmarks with published results for both. Gemini 2.5 Flash-Lite scores higher in 0 categories and o3 in 10 categories; 10 gaps are clear of the uncertainty.
- The widest gap is in knowledge, where o3 leads 54.6 to 32.5.
- The biggest single-benchmark swing is GPQA (HELM): 30.9% for Gemini 2.5 Flash-Lite and 75.3% for o3.
- Gemini 2.5 Flash-Lite is cheaper at $0.10 / $0.40 per million input/output tokens, against $2 / $8 for o3.
- Gemini 2.5 Flash-Lite accepts more context: 1.05M tokens versus 200K.

## Snapshot

| | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| Provider | Google | OpenAI |
| Noometry Index | 37.0 | 47.5 |
| Rank | 211 | 61 |
| Context | 1.05M | 200K |
| Input $/M | $0.10 | $2 |
| Output $/M | $0.40 | $8 |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 2.5 Flash-Lite: 38.5 (#173)
- o3: 46.8 (#64)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| WeirdML | 35.2% | 52.4% |
| LMArena Coding | 1373 | 1408 |
| ALE-Bench | 325.9 | 933.55 |
| SWE-bench Verified | — | 62.3% |
| SWE-bench Verified (bash only) | — | 58.4% |
| Aider Polyglot | — | 81.3% |
| GSO | — | 8.8% |
| CadEval | — | 74% |

## Agentic & Tool Use

- Gemini 2.5 Flash-Lite: 28.0 (#96)
- o3: 34.5 (#44)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| Berkeley Function Calling Leaderboard | 36.9% | 63% |
| GDPval | — | 30.8% |
| DeepResearch Bench | — | 45.2% |
| OSWorld | — | 23% |
| LMArena Search | — | 1144 |
| METR Time Horizons | — | 65.4% |

## Reasoning

- Gemini 2.5 Flash-Lite: 22.2 (#205)
- o3: 32.0 (#78)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| Kagi LLM Benchmark | 40.5% | 67.6% |
| LMArena Hard Prompts | 1377 | 1402 |
| DTBench | 62.8% | 84.8% |
| LMCA | 18.1% | 39.7% |
| Epoch Capabilities Index | 133.94 | 146.86 |
| ARC-AGI-2 | — | 6.5% |
| SimpleBench | — | 53.1% |
| ARC-AGI-1 | — | 60.8% |
| CritPt | — | 1.4% |
| Chess Puzzles | — | 38% |
| EnigmaEval | — | 13.1% |
| Mystery Game Puzzles | — | 29% |
| ForecastBench | — | 62.5 |

## Math

- Gemini 2.5 Flash-Lite: 38.0 (#144)
- o3: 50.2 (#58)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| Omni-MATH | 48% | 71.4% |
| LMArena Math | 1373 | 1426 |
| FrontierMath (Tiers 1-3) | — | 33.3% |
| OTIS Mock AIME 2024-2025 | — | 84.4% |
| MATH Level 5 | — | 97.8% |
| FrontierMath (Feb 2025 set) | — | 18.7% |
| FrontierMath Tier 4 (v1) | — | 2.1% |

## Knowledge

- Gemini 2.5 Flash-Lite: 32.5 (#210)
- o3: 54.6 (#52)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| MMLU-Pro | 53.7% | 85.9% |
| GPQA (HELM) | 30.9% | 75.3% |
| LMArena Expert | 1373 | 1402 |
| GPQA Diamond | — | 81.8% |
| Humanity's Last Exam | — | 20.3% |
| SimpleQA Verified | — | 49.4% |
| Confabulations | — | 14.4% |
| Vectara Hallucination Rate | 3.3% | — |

## Multimodal

- Gemini 2.5 Flash-Lite: 29.1 (#114)
- o3: 41.4 (#36)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| LMArena Vision | 1198 | 1214 |
| VPCT | 30% | 52% |
| GeoBench | — | 74% |

## Multilingual

- Gemini 2.5 Flash-Lite: 49.3 (#134)
- o3: 51.7 (#105)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| LMArena Non-English | 1369 | 1401 |
| LMArena Chinese | 1404 | 1437 |
| LMArena French | 1388 | 1430 |
| LMArena German | 1389 | 1420 |
| LMArena Japanese | 1359 | 1403 |
| LMArena Korean | 1360 | 1370 |
| LMArena Russian | 1373 | 1406 |
| LMArena Spanish | 1396 | 1395 |

## Instruction Following

- Gemini 2.5 Flash-Lite: 70.0 (#168)
- o3: 72.8 (#127)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| IFEval | 81% | 86.9% |
| LMArena Instruction Following | 1367 | 1368 |

## Long Context

- Gemini 2.5 Flash-Lite: 33.3 (#262)
- o3: 53.3 (#6)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| Fiction.LiveBench | 47.2% | 88.9% |
| LMArena Longer Query | 1373 | 1372 |
| CL-bench | — | 17.8% |

## Writing & Preference

- Gemini 2.5 Flash-Lite: 56.8 (#135)
- o3: 63.5 (#64)

| Benchmark | Gemini 2.5 Flash-Lite | o3 |
|---|---|---|
| LMArena Text | 1379 | 1410 |
| LMArena Creative Writing | 1367 | 1359 |
| WildBench | 81.8% | 86.1% |
| LMArena Multi-Turn | 1366 | 1405 |
| Short-Story Creative Writing | — | 83.9% |
| EQ-Bench Creative Writing | — | 1676 |

## FAQ

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

o3 is the stronger model overall, scoring 47.5 to 37.0 on the Noometry Index. Gemini 2.5 Flash-Lite costs 20× less per token, which makes it the better buy when o3's lead doesn't matter for your workload.

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

Gemini 2.5 Flash-Lite is cheaper. It lists at $0.10 per million input tokens and $0.40 per million output tokens; o3 lists at $2 and $8.

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

o3 scores higher on coding benchmarks: 46.8 versus 38.5 in the Noometry coding category.

### Which has the bigger context window?

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

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

32 benchmarks have published results for both models. Gemini 2.5 Flash-Lite has 33 scored results on Noometry and o3 has 63.