# Claude 3 Sonnet vs Grok 4.1 Fast

> Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 29.0 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-3-sonnet-vs-grok-4-1-fast
- Last updated: 2026-10-12
- Shared benchmarks: 19

## Summary

- They share 19 benchmarks with published results for both. Claude 3 Sonnet scores higher in 0 categories and Grok 4.1 Fast in 9 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.1 Fast leads 43.4 to 20.5.
- The biggest single-benchmark swing is DTBench: 53.6% for Claude 3 Sonnet and 87.7% for Grok 4.1 Fast.

## Snapshot

| | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 29.0 | 41.4 |
| Rank | 319 | 136 |
| Context | — | 128K |
| Input $/M | — | $0.20 |
| Output $/M | — | $0.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude 3 Sonnet: 29.6 (#302)
- Grok 4.1 Fast: 34.1 (#245)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Coding | 1223 | 1411 |
| LMArena WebDev | — | 1242 |
| WeirdML | 10.2% | — |
| BigCodeBench Instruct | 42.7% | — |
| BigCodeBench Complete | 53.8% | — |
| ALE-Bench | — | 394.93 |
| HumanEval+ | 64% | — |
| MBPP+ | 69.3% | — |

## Agentic & Tool Use

- Claude 3 Sonnet: —
- Grok 4.1 Fast: 36.3 (#39)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| Berkeley Function Calling Leaderboard | — | 69.6% |
| τ²-bench Banking | — | 13.1% |
| LMArena Search | — | 1171 |
| Vending-Bench 2 | — | 1,107 |

## Reasoning

- Claude 3 Sonnet: 20.5 (#237)
- Grok 4.1 Fast: 43.4 (#49)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Hard Prompts | 1197 | 1407 |
| DTBench | 53.6% | 87.7% |
| SimpleBench | — | 56% |
| NYT Connections (extended) | — | 87.4% |
| Epoch Capabilities Index | 120.7 | — |
| ForecastBench | — | 61 |
| WinoGrande | 75.1% | — |

## Math

- Claude 3 Sonnet: 10.7 (#310)
- Grok 4.1 Fast: 31.9 (#221)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Math | 1213 | 1408 |
| MathArena Final-Answer Competitions | — | 60.9% |
| OTIS Mock AIME 2024-2025 | 2.5% | — |
| ProofBench | — | 4% |
| MATH Level 5 | 18.2% | — |

## Knowledge

- Claude 3 Sonnet: 21.1 (#276)
- Grok 4.1 Fast: 33.1 (#207)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Expert | 1173 | 1399 |
| GPQA Diamond | 40.6% | — |
| Vectara Hallucination Rate | — | 17.8% |
| MMLU | 75.9% | — |

## Multimodal

- Claude 3 Sonnet: 25.2 (#125)
- Grok 4.1 Fast: 37.0 (#76)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Vision | 984 | 1201 |

## Multilingual

- Claude 3 Sonnet: 37.8 (#234)
- Grok 4.1 Fast: 51.0 (#114)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Non-English | 1205 | 1391 |
| LMArena Chinese | 1189 | 1441 |
| LMArena French | 1229 | 1415 |
| LMArena German | 1204 | 1404 |
| LMArena Japanese | 1131 | 1349 |
| LMArena Korean | 1128 | 1361 |
| LMArena Russian | 1227 | 1387 |
| LMArena Spanish | 1204 | 1413 |

## Instruction Following

- Claude 3 Sonnet: 62.8 (#235)
- Grok 4.1 Fast: 72.7 (#133)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Instruction Following | 1199 | 1376 |

## Long Context

- Claude 3 Sonnet: 36.7 (#228)
- Grok 4.1 Fast: 42.4 (#126)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Longer Query | 1211 | 1390 |

## Writing & Preference

- Claude 3 Sonnet: 42.1 (#238)
- Grok 4.1 Fast: 57.2 (#131)

| Benchmark | Claude 3 Sonnet | Grok 4.1 Fast |
|---|---|---|
| LMArena Text | 1218 | 1408 |
| LMArena Creative Writing | 1186 | 1394 |
| LMArena Multi-Turn | 1227 | 1389 |
| EQ-Bench Creative Writing | — | 1327 |

## FAQ

### Is Claude 3 Sonnet better than Grok 4.1 Fast?

Grok 4.1 Fast is the stronger model overall, scoring 41.4 to 29.0 on the Noometry Index.

### Is Claude 3 Sonnet or Grok 4.1 Fast better for coding?

Grok 4.1 Fast scores higher on coding benchmarks: 34.1 versus 29.6 in the Noometry coding category.

### How many benchmarks do Claude 3 Sonnet and Grok 4.1 Fast share?

19 benchmarks have published results for both models. Claude 3 Sonnet has 30 scored results on Noometry and Grok 4.1 Fast has 32.