# Claude Opus 4.6 vs Grok 4 Fast

> Claude Opus 4.6 is the stronger model overall, scoring 58.3 to 39.0 on the Noometry Index.

- Canonical page: https://noometry.com/compare/claude-opus-4-6-vs-grok-4-fast
- Last updated: 2026-10-10
- Shared benchmarks: 29

## Summary

- They share 29 benchmarks with published results for both. Claude Opus 4.6 scores higher in 8 categories and Grok 4 Fast in 1 category; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Claude Opus 4.6 leads 57.7 to 22.5.
- The biggest single-benchmark swing is ARC-AGI-2: 69.2% for Claude Opus 4.6 and 5.3% for Grok 4 Fast.

## Snapshot

| | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 58.3 | 39.0 |
| Rank | 18 | 164 |
| Context | 1M | — |
| Input $/M | $5 | — |
| Output $/M | $25 | — |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Opus 4.6: 57.7 (#15)
- Grok 4 Fast: 32.3 (#264)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| LMArena WebDev | 1546 | 1160 |
| WeirdML | 78% | 42.9% |
| LMArena Coding | 1535 | 1429 |
| SWE-bench Verified | 78.7% | — |
| FrontierCode | 26.6% | — |
| SWE-bench Verified (bash only) | 75.6% | — |
| SWE-bench Multilingual | 72% | — |
| GSO | 41.2% | — |
| ALE-Bench | 996.5 | — |
| AlgoTune | 1.47 | — |

## Agentic & Tool Use

- Claude Opus 4.6: 51.0 (#4)
- Grok 4 Fast: 29.3 (#80)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| τ²-bench Banking | 27.3% | 15.7% |
| Cybench | 93% | 30% |
| LMArena Search | 1253 | 1171 |
| Terminal-Bench | 79.8% | — |
| APEX-Agents | 46.3% | — |
| Remote Labor Index | 4.2% | — |
| DeepResearch Bench | 55.3% | — |
| GBAEval | 44.1% | — |
| METR Time Horizons | 78.9% | — |
| Vending-Bench 2 | 8,018 | — |

## Reasoning

- Claude Opus 4.6: 57.7 (#21)
- Grok 4 Fast: 22.5 (#179)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| ARC-AGI-2 | 69.2% | 5.3% |
| Kagi LLM Benchmark | 83.6% | 66.1% |
| ARC-AGI-1 | 94% | 48.5% |
| LMArena Hard Prompts | 1527 | 1413 |
| DTBench | 91.2% | 82.7% |
| Epoch Capabilities Index | 155.36 | 144.21 |
| ForecastBench | 60 | 60.5 |
| SimpleBench | 67.6% | — |
| NYT Connections (extended) | 92.1% | — |
| Chess Puzzles | 17% | — |
| EnigmaEval | 7.6% | — |
| Thematic Generalization | 80.6% | — |
| EBR-Bench | 12.7% | — |
| Mystery Game Puzzles | 25% | — |
| LMCA | 55.8% | — |

## Math

- Claude Opus 4.6: 62.7 (#25)
- Grok 4 Fast: 36.1 (#126)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| LMArena Math | 1517 | 1419 |
| FrontierMath (Tiers 1-3) | 66% | — |
| FrontierMath Tier 4 | 26.8% | — |
| MathArena Final-Answer Competitions | 78.5% | — |
| OTIS Mock AIME 2024-2025 | 94.4% | — |
| ProofBench | 50% | — |
| FrontierMath (Feb 2025 set) | 40.7% | — |
| FrontierMath Tier 4 (v1) | 22.9% | — |

## Knowledge

- Claude Opus 4.6: 61.8 (#23)
- Grok 4 Fast: 31.5 (#211)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| Vectara Hallucination Rate | 12.2% | 19.7% |
| LMArena Expert | 1546 | 1411 |
| GPQA Diamond | 90.5% | — |
| Humanity's Last Exam | 34.4% | — |
| SimpleQA Verified | 47% | — |

## Multimodal

- Claude Opus 4.6: 37.0 (#67)
- Grok 4 Fast: —

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| LMArena Vision | 1316 | — |
| Furniture Assembly | 28.3% | — |
| LMArena Document | 1507 | — |

## Multilingual

- Claude Opus 4.6: 58.2 (#4)
- Grok 4 Fast: 51.5 (#106)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| LMArena Non-English | 1490 | 1397 |
| LMArena Chinese | 1551 | 1458 |
| LMArena French | 1513 | 1433 |
| LMArena German | 1504 | 1383 |
| LMArena Japanese | 1484 | 1358 |
| LMArena Korean | 1465 | 1359 |
| LMArena Russian | 1497 | 1387 |
| LMArena Spanish | 1512 | 1414 |

## Instruction Following

- Claude Opus 4.6: 79.7 (#3)
- Grok 4 Fast: 73.4 (#116)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| LMArena Instruction Following | 1523 | 1388 |

## Long Context

- Claude Opus 4.6: 48.1 (#13)
- Grok 4 Fast: 63.2 (#3)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| LMArena Longer Query | 1520 | 1415 |
| Fiction.LiveBench | — | 94.4% |
| CL-bench | 20.7% | — |
| CL-bench Life | 17% | — |

## Writing & Preference

- Claude Opus 4.6: 73.7 (#9)
- Grok 4 Fast: 60.2 (#96)

| Benchmark | Claude Opus 4.6 | Grok 4 Fast |
|---|---|---|
| LMArena Text | 1504 | 1407 |
| LMArena Creative Writing | 1506 | 1388 |
| LMArena Multi-Turn | 1514 | 1414 |
| EQ-Bench Creative Writing | 1809 | — |
| EQ-Bench 4 | 1223 | — |

## FAQ

### Is Claude Opus 4.6 better than Grok 4 Fast?

Claude Opus 4.6 is the stronger model overall, scoring 58.3 to 39.0 on the Noometry Index.

### Is Claude Opus 4.6 or Grok 4 Fast better for coding?

Claude Opus 4.6 scores higher on coding benchmarks: 57.7 versus 32.3 in the Noometry coding category.

### How many benchmarks do Claude Opus 4.6 and Grok 4 Fast share?

29 benchmarks have published results for both models. Claude Opus 4.6 has 68 scored results on Noometry and Grok 4 Fast has 30.