# Gemini 1.5 Pro (May 2024) vs Gemini 2.5 Flash

> Gemini 2.5 Flash is the stronger model overall, scoring 39.3 to 32.1 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gemini-1-5-pro-vs-gemini-2-5-flash
- Last updated: 2026-10-10
- Shared benchmarks: 34

## Summary

- They share 34 benchmarks with published results for both. Gemini 1.5 Pro (May 2024) scores higher in 0 categories and Gemini 2.5 Flash in 10 categories; 10 gaps are clear of the uncertainty.
- The widest gap is in math, where Gemini 2.5 Flash leads 39.9 to 25.8.
- The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 23.1% for Gemini 1.5 Pro (May 2024) and 73.1% for Gemini 2.5 Flash.

## Snapshot

| | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| Provider | Google | Google |
| Noometry Index | 32.1 | 39.3 |
| Rank | 261 | 170 |
| Context | — | 1.05M |
| Input $/M | — | $0.30 |
| Output $/M | — | $2.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Gemini 1.5 Pro (May 2024): 34.2 (#241)
- Gemini 2.5 Flash: 35.8 (#220)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| WeirdML | 22.2% | 41.9% |
| LMArena Coding | 1294 | 1424 |
| SWE-bench Verified (bash only) | — | 28.7% |
| Aider Polyglot | — | 55.1% |
| BigCodeBench Instruct | 43.8% | — |
| BigCodeBench Complete | 57.5% | — |
| CadEval | 34% | — |
| ALE-Bench | — | 661.88 |
| HumanEval+ | 79.3% | — |
| MBPP+ | 74.6% | — |

## Agentic & Tool Use

- Gemini 1.5 Pro (May 2024): 17.9 (#145)
- Gemini 2.5 Flash: 30.8 (#74)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| TheAgentCompany | 3.4% | 41.1% |
| BALROG | 21% | 33.5% |
| Terminal-Bench | — | 17.1% |
| Berkeley Function Calling Leaderboard | — | 56.2% |
| Cybench | 7.5% | — |
| Vending-Bench 2 | — | 548.84 |

## Reasoning

- Gemini 1.5 Pro (May 2024): 12.3 (#338)
- Gemini 2.5 Flash: 18.1 (#286)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| ARC-AGI-2 | 0.8% | 2.5% |
| SimpleBench | 27.1% | 41.2% |
| LMArena Hard Prompts | 1296 | 1422 |
| DTBench | 59% | 76.5% |
| Epoch Capabilities Index | 131.73 | 143.03 |
| ForecastBench | 58.4 | 60.6 |
| Kagi LLM Benchmark | — | 56.8% |
| ARC-AGI-1 | — | 33.3% |
| CritPt | — | 1.1% |
| EnigmaEval | — | 2.7% |
| LMCA | — | 27.5% |
| BIG-Bench Hard | 89.2% | — |

## Math

- Gemini 1.5 Pro (May 2024): 25.8 (#266)
- Gemini 2.5 Flash: 39.9 (#98)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 23.1% | 73.1% |
| Omni-MATH | 36.4% | 38.5% |
| LMArena Math | 1315 | 1415 |
| MATH Level 5 | 70.4% | — |
| FrontierMath (Feb 2025 set) | — | 4.8% |
| FrontierMath Tier 4 (v1) | — | 4.2% |

## Knowledge

- Gemini 1.5 Pro (May 2024): 29.4 (#239)
- Gemini 2.5 Flash: 36.4 (#168)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| Humanity's Last Exam | 4.6% | 12.1% |
| MMLU-Pro | 73.7% | 63.9% |
| Confabulations | 13.5% | 16.8% |
| GPQA (HELM) | 53.4% | 39% |
| LMArena Expert | 1279 | 1426 |
| GPQA Diamond | 57.2% | — |
| Vectara Hallucination Rate | — | 7.8% |
| MMLU | 86.9% | — |

## Multimodal

- Gemini 1.5 Pro (May 2024): 36.8 (#77)
- Gemini 2.5 Flash: 41.8 (#32)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| LMArena Vision | 1161 | 1253 |
| Video-MME | 75% | — |
| GeoBench | — | 76% |
| VPCT | — | 46.2% |
| SpatialViz-Bench | — | 36.9% |

## Multilingual

- Gemini 1.5 Pro (May 2024): 45.3 (#174)
- Gemini 2.5 Flash: 52.3 (#88)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| LMArena Non-English | 1312 | 1409 |
| LMArena Chinese | 1331 | 1450 |
| LMArena French | 1302 | 1433 |
| LMArena German | 1286 | 1418 |
| LMArena Japanese | 1292 | 1405 |
| LMArena Korean | 1298 | 1385 |
| LMArena Russian | 1320 | 1415 |
| LMArena Spanish | 1311 | 1421 |

## Instruction Following

- Gemini 1.5 Pro (May 2024): 68.6 (#185)
- Gemini 2.5 Flash: 75.7 (#54)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| IFEval | 83.7% | 89.8% |
| LMArena Instruction Following | 1297 | 1405 |

## Long Context

- Gemini 1.5 Pro (May 2024): 39.8 (#169)
- Gemini 2.5 Flash: 47.5 (#17)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| LMArena Longer Query | 1308 | 1419 |
| Fiction.LiveBench | — | 77.8% |

## Writing & Preference

- Gemini 1.5 Pro (May 2024): 52.4 (#172)
- Gemini 2.5 Flash: 53.8 (#157)

| Benchmark | Gemini 1.5 Pro (May 2024) | Gemini 2.5 Flash |
|---|---|---|
| LMArena Text | 1319 | 1417 |
| LMArena Creative Writing | 1333 | 1400 |
| WildBench | 81.3% | 81.7% |
| LMArena Multi-Turn | 1296 | 1408 |
| Short-Story Creative Writing | — | 76.5% |
| EQ-Bench Creative Writing | — | 1137 |

## FAQ

### Is Gemini 1.5 Pro (May 2024) better than Gemini 2.5 Flash?

Gemini 2.5 Flash is the stronger model overall, scoring 39.3 to 32.1 on the Noometry Index.

### Is Gemini 1.5 Pro (May 2024) or Gemini 2.5 Flash better for coding?

Gemini 2.5 Flash scores higher on coding benchmarks: 35.8 versus 34.2 in the Noometry coding category.

### How many benchmarks do Gemini 1.5 Pro (May 2024) and Gemini 2.5 Flash share?

34 benchmarks have published results for both models. Gemini 1.5 Pro (May 2024) has 45 scored results on Noometry and Gemini 2.5 Flash has 54.