# Claude 2.1 vs Grok 4.1 Fast

> Grok 4.1 Fast is the stronger model overall, scoring 40.9 to 24.9 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-2-1-vs-grok-4-1-fast
- Last updated: 2026-10-10
- Shared benchmarks: 2

## Summary

- They share 2 benchmarks with published results for both. Claude 2.1 scores higher in 0 categories and Grok 4.1 Fast in 4 categories; 4 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.1 Fast leads 42.3 to 20.6.
- The biggest single-benchmark swing is DTBench: 51% for Claude 2.1 and 87.7% for Grok 4.1 Fast.

## Snapshot

| | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 24.9 | 40.9 |
| Rank | 340 | 131 |
| Context | — | 128K |
| Input $/M | — | $0.20 |
| Output $/M | — | $0.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude 2.1: 25.8 (#322)
- Grok 4.1 Fast: 33.8 (#236)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| LMArena WebDev | — | 1241 |
| WeirdML | 7.1% | — |
| LMArena Coding | — | 1411 |
| ALE-Bench | — | 394.93 |

## Agentic & Tool Use

- Claude 2.1: —
- Grok 4.1 Fast: 36.1 (#35)

| Benchmark | Claude 2.1 | 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 2.1: 20.6 (#216)
- Grok 4.1 Fast: 42.3 (#45)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| DTBench | 51% | 87.7% |
| ForecastBench | 54.2 | 61 |
| SimpleBench | — | 56% |
| NYT Connections (extended) | — | 87.4% |
| LMArena Hard Prompts | — | 1407 |
| Epoch Capabilities Index | 119.22 | — |

## Math

- Claude 2.1: 9.6 (#309)
- Grok 4.1 Fast: 30.9 (#201)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| MathArena Final-Answer Competitions | — | 60.9% |
| OTIS Mock AIME 2024-2025 | 1.9% | — |
| ProofBench | — | 4% |
| LMArena Math | — | 1408 |

## Knowledge

- Claude 2.1: 15.5 (#287)
- Grok 4.1 Fast: 32.6 (#203)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| GPQA Diamond | 33% | — |
| Vectara Hallucination Rate | — | 17.8% |
| LMArena Expert | — | 1398 |
| MMLU | 73.5% | — |

## Multimodal

- Claude 2.1: —
- Grok 4.1 Fast: 36.3 (#71)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| LMArena Vision | — | 1201 |

## Multilingual

- Claude 2.1: —
- Grok 4.1 Fast: 51.1 (#110)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| LMArena Non-English | — | 1391 |
| LMArena Chinese | — | 1441 |
| LMArena French | — | 1416 |
| LMArena German | — | 1404 |
| LMArena Japanese | — | 1347 |
| LMArena Korean | — | 1361 |
| LMArena Russian | — | 1387 |
| LMArena Spanish | — | 1411 |

## Instruction Following

- Claude 2.1: —
- Grok 4.1 Fast: 72.8 (#127)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| LMArena Instruction Following | — | 1376 |

## Long Context

- Claude 2.1: —
- Grok 4.1 Fast: 42.4 (#121)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| LMArena Longer Query | — | 1390 |

## Writing & Preference

- Claude 2.1: —
- Grok 4.1 Fast: 57.4 (#126)

| Benchmark | Claude 2.1 | Grok 4.1 Fast |
|---|---|---|
| LMArena Text | — | 1408 |
| LMArena Creative Writing | — | 1394 |
| EQ-Bench Creative Writing | — | 1327 |
| LMArena Multi-Turn | — | 1389 |

## FAQ

### Is Claude 2.1 better than Grok 4.1 Fast?

Grok 4.1 Fast is the stronger model overall, scoring 40.9 to 24.9 on the Noometry Index.

### Is Claude 2.1 or Grok 4.1 Fast better for coding?

Grok 4.1 Fast scores higher on coding benchmarks: 33.8 versus 25.8 in the Noometry coding category.

### How many benchmarks do Claude 2.1 and Grok 4.1 Fast share?

2 benchmarks have published results for both models. Claude 2.1 has 7 scored results on Noometry and Grok 4.1 Fast has 32.