# Claude Opus 4.1 vs Gemini 2.5 Flash

> Claude Opus 4.1 is the stronger model overall, scoring 40.8 to 39.0 on the Noometry Index. Gemini 2.5 Flash costs 35× less per token, which makes it the better buy when Claude Opus 4.1's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-opus-4-1-vs-gemini-2-5-flash
- Last updated: 2026-10-10
- Shared benchmarks: 34

## Summary

- They share 34 benchmarks with published results for both. Claude Opus 4.1 scores higher in 5 categories and Gemini 2.5 Flash in 5 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in math, where Gemini 2.5 Flash leads 38.1 to 22.0.
- The biggest single-benchmark swing is Terminal-Bench: 38% for Claude Opus 4.1 and 17.1% for Gemini 2.5 Flash.
- Gemini 2.5 Flash is cheaper at $0.30 / $2.50 per million input/output tokens, against $15 / $75 for Claude Opus 4.1.
- Gemini 2.5 Flash accepts more context: 1.05M tokens versus 200K.

## Snapshot

| | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| Provider | Anthropic | Google |
| Noometry Index | 40.8 | 39.0 |
| Rank | 136 | 162 |
| Context | 200K | 1.05M |
| Input $/M | $15 | $0.30 |
| Output $/M | $75 | $2.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Opus 4.1: 44.3 (#69)
- Gemini 2.5 Flash: 35.5 (#210)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| WeirdML | 45.9% | 41.9% |
| LMArena Coding | 1479 | 1424 |
| ALE-Bench | 674.77 | 661.88 |
| SWE-bench Verified | 73.3% | — |
| SWE-bench Verified (bash only) | — | 28.7% |
| Aider Polyglot | — | 55.1% |
| LMArena WebDev | 1390 | — |
| AlgoTune | 1.34 | — |

## Agentic & Tool Use

- Claude Opus 4.1: 34.8 (#38)
- Gemini 2.5 Flash: 30.6 (#67)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| Terminal-Bench | 38% | 17.1% |
| Berkeley Function Calling Leaderboard | — | 56.2% |
| GDPval | 43.6% | — |
| TheAgentCompany | — | 41.1% |
| Cybench | 42% | — |
| DeepResearch Bench | 48.3% | — |
| BALROG | — | 33.5% |
| LMArena Search | 1148 | — |
| METR Time Horizons | 66.8% | — |
| Vending-Bench 2 | — | 548.84 |

## Reasoning

- Claude Opus 4.1: 31.6 (#70)
- Gemini 2.5 Flash: 18.2 (#271)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| SimpleBench | 60% | 41.2% |
| EnigmaEval | 7.2% | 2.7% |
| LMArena Hard Prompts | 1443 | 1422 |
| DTBench | 80% | 76.5% |
| LMCA | 37.1% | 27.5% |
| Epoch Capabilities Index | 144.11 | 143.04 |
| ForecastBench | 62 | 60.6 |
| ARC-AGI-2 | — | 2.5% |
| Kagi LLM Benchmark | — | 56.8% |
| ARC-AGI-1 | — | 33.3% |
| CritPt | — | 1.1% |
| Chess Puzzles | 7% | — |
| EBR-Bench | 7.9% | — |
| Mystery Game Puzzles | 21% | — |

## Math

- Claude Opus 4.1: 22.0 (#267)
- Gemini 2.5 Flash: 38.1 (#87)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 68.9% | 73.1% |
| LMArena Math | 1430 | 1415 |
| FrontierMath (Feb 2025 set) | 7.2% | 4.8% |
| FrontierMath Tier 4 (v1) | 4.2% | 4.2% |
| FrontierMath (Tiers 1-3) | 12.6% | — |
| FrontierMath Tier 4 | 2.4% | — |
| Omni-MATH | — | 38.5% |

## Knowledge

- Claude Opus 4.1: 41.9 (#93)
- Gemini 2.5 Flash: 36.1 (#162)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| Humanity's Last Exam | 11.5% | 12.1% |
| Confabulations | 17.1% | 16.8% |
| Vectara Hallucination Rate | 11.8% | 7.8% |
| LMArena Expert | 1439 | 1426 |
| GPQA Diamond | 77.3% | — |
| MMLU-Pro | — | 63.9% |
| GPQA (HELM) | — | 39% |

## Multimodal

- Claude Opus 4.1: 26.2 (#114)
- Gemini 2.5 Flash: 41.2 (#31)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| VPCT | 35% | 46.2% |
| LMArena Vision | — | 1254 |
| GeoBench | — | 76% |
| SpatialViz-Bench | — | 36.9% |

## Multilingual

- Claude Opus 4.1: 52.1 (#90)
- Gemini 2.5 Flash: 52.5 (#83)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| LMArena Non-English | 1405 | 1410 |
| LMArena Chinese | 1427 | 1450 |
| LMArena French | 1432 | 1433 |
| LMArena German | 1412 | 1419 |
| LMArena Japanese | 1378 | 1403 |
| LMArena Korean | 1381 | 1385 |
| LMArena Russian | 1421 | 1415 |
| LMArena Spanish | 1448 | 1421 |

## Instruction Following

- Claude Opus 4.1: 75.8 (#53)
- Gemini 2.5 Flash: 75.9 (#50)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| LMArena Instruction Following | 1436 | 1405 |
| IFEval | — | 89.8% |

## Long Context

- Claude Opus 4.1: 44.5 (#60)
- Gemini 2.5 Flash: 47.5 (#16)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| LMArena Longer Query | 1455 | 1419 |
| Fiction.LiveBench | — | 77.8% |

## Writing & Preference

- Claude Opus 4.1: 62.6 (#70)
- Gemini 2.5 Flash: 54.0 (#153)

| Benchmark | Claude Opus 4.1 | Gemini 2.5 Flash |
|---|---|---|
| LMArena Text | 1419 | 1417 |
| LMArena Creative Writing | 1412 | 1400 |
| Short-Story Creative Writing | 84.7% | 76.5% |
| LMArena Multi-Turn | 1444 | 1408 |
| EQ-Bench Creative Writing | — | 1137 |
| WildBench | — | 81.7% |

## FAQ

### Is Claude Opus 4.1 better than Gemini 2.5 Flash?

Claude Opus 4.1 is the stronger model overall, scoring 40.8 to 39.0 on the Noometry Index. Gemini 2.5 Flash costs 35× less per token, which makes it the better buy when Claude Opus 4.1's lead doesn't matter for your workload.

### Which is cheaper, Claude Opus 4.1 or Gemini 2.5 Flash?

Gemini 2.5 Flash is cheaper. It lists at $0.30 per million input tokens and $2.50 per million output tokens; Claude Opus 4.1 lists at $15 and $75.

### Is Claude Opus 4.1 or Gemini 2.5 Flash better for coding?

Claude Opus 4.1 scores higher on coding benchmarks: 44.3 versus 35.5 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 Claude Opus 4.1 and Gemini 2.5 Flash share?

34 benchmarks have published results for both models. Claude Opus 4.1 has 48 scored results on Noometry and Gemini 2.5 Flash has 54.