# Claude Opus 4.5 vs Grok 4.20 (Non-Reasoning)

> Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 48.6 on the Noometry Index. Grok 4.20 (Non-Reasoning) costs 6.4× less per token, which makes it the better buy when Claude Opus 4.5's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-opus-4-5-vs-grok-4-20
- Last updated: 2026-10-10
- Shared benchmarks: 42

## Summary

- They share 42 benchmarks with published results for both. Claude Opus 4.5 scores higher in 6 categories and Grok 4.20 (Non-Reasoning) in 4 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in agentic & tool use, where Claude Opus 4.5 leads 47.3 to 34.4.
- The biggest single-benchmark swing is NYT Connections (extended): 52.5% for Claude Opus 4.5 and 85.4% for Grok 4.20 (Non-Reasoning).
- Grok 4.20 (Non-Reasoning) is cheaper at $1.25 / $2.50 per million input/output tokens, against $5 / $25 for Claude Opus 4.5.
- Grok 4.20 (Non-Reasoning) accepts more context: 1M tokens versus 200K.

## Snapshot

| | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 50.5 | 48.6 |
| Rank | 47 | 54 |
| Context | 200K | 1M |
| Input $/M | $5 | $1.25 |
| Output $/M | $25 | $2.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Opus 4.5: 54.8 (#27)
- Grok 4.20 (Non-Reasoning): 42.1 (#112)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena WebDev | 1494 | 1375 |
| WeirdML | 63.7% | 52.3% |
| LMArena Coding | 1504 | 1459 |
| ALE-Bench | 1,025 | 1,150 |
| SWE-bench Verified | 76.7% | — |
| SWE-bench Verified (bash only) | 76.8% | — |
| SWE-bench Multilingual | 70.7% | — |
| GSO | 26.5% | — |
| AlgoTune | 1.77 | — |

## Agentic & Tool Use

- Claude Opus 4.5: 47.3 (#12)
- Grok 4.20 (Non-Reasoning): 34.4 (#46)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| Terminal-Bench | 63.1% | 57.3% |
| τ²-bench Banking | 24.7% | 18% |
| LMArena Search | 1180 | 1189 |
| Vending-Bench 2 | 4,967 | 4,663 |
| Berkeley Function Calling Leaderboard | 77.5% | — |
| GDPval | 45.5% | — |
| Remote Labor Index | 3.8% | — |
| τ²-bench Airline | 84% | — |
| τ²-bench Retail | 79.6% | — |
| τ²-bench Telecom | 92.3% | — |
| Cybench | 82% | — |
| DeepResearch Bench | 54.8% | — |
| OSWorld | 66.3% | — |
| BALROG | 43.5% | — |
| METR Time Horizons | 75% | — |

## Reasoning

- Claude Opus 4.5: 42.6 (#51)
- Grok 4.20 (Non-Reasoning): 52.3 (#32)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| ARC-AGI-2 | 37.6% | 65.1% |
| Kagi LLM Benchmark | 80.2% | 75% |
| NYT Connections (extended) | 52.5% | 85.4% |
| ARC-AGI-1 | 80% | 89.5% |
| Chess Puzzles | 12% | 24% |
| LMArena Hard Prompts | 1476 | 1451 |
| DTBench | 89.9% | 90.1% |
| LMCA | 44.5% | 38.7% |
| Epoch Capabilities Index | 150.09 | 151.98 |
| ForecastBench | 60.7 | 61.4 |
| SimpleBench | 62% | — |
| EnigmaEval | 11.9% | — |
| Thematic Generalization | — | 63.8% |
| EBR-Bench | 14.3% | — |
| Mystery Game Puzzles | 22% | — |

## Math

- Claude Opus 4.5: 38.6 (#132)
- Grok 4.20 (Non-Reasoning): 48.2 (#65)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| FrontierMath (Tiers 1-3) | 34.4% | 44.9% |
| FrontierMath Tier 4 | 4.9% | 17.1% |
| OTIS Mock AIME 2024-2025 | 86.1% | 92.2% |
| ProofBench | 36% | 14% |
| LMArena Math | 1463 | 1455 |
| FrontierMath (Feb 2025 set) | 20.7% | — |
| FrontierMath Tier 4 (v1) | 4.2% | — |

## Knowledge

- Claude Opus 4.5: 56.5 (#44)
- Grok 4.20 (Non-Reasoning): 52.8 (#60)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| GPQA Diamond | 86% | 89.3% |
| SimpleQA Verified | 45.7% | 30.2% |
| LMArena Expert | 1487 | 1439 |
| Humanity's Last Exam | 25.2% | — |
| Vectara Hallucination Rate | 10.9% | — |

## Multimodal

- Claude Opus 4.5: 31.4 (#107)
- Grok 4.20 (Non-Reasoning): 33.3 (#98)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Document | 1462 | 1416 |
| LMArena Vision | — | 1263 |
| GeoBench | 75% | — |
| VPCT | 40% | — |
| Blueprint-Bench 2 | — | 0% |
| Furniture Assembly | 28.3% | — |

## Multilingual

- Claude Opus 4.5: 54.3 (#47)
- Grok 4.20 (Non-Reasoning): 54.5 (#40)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Non-English | 1438 | 1441 |
| LMArena Chinese | 1470 | 1481 |
| LMArena French | 1471 | 1476 |
| LMArena German | 1449 | 1465 |
| LMArena Japanese | 1416 | 1449 |
| LMArena Korean | 1424 | 1417 |
| LMArena Russian | 1447 | 1458 |
| LMArena Spanish | 1458 | 1443 |

## Instruction Following

- Claude Opus 4.5: 77.5 (#19)
- Grok 4.20 (Non-Reasoning): 74.8 (#83)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Instruction Following | 1478 | 1420 |

## Long Context

- Claude Opus 4.5: 46.5 (#22)
- Grok 4.20 (Non-Reasoning): 45.5 (#34)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| CL-bench | 21.1% | 22.2% |
| LMArena Longer Query | 1480 | 1437 |
| CL-bench Life | — | 11.9% |

## Writing & Preference

- Claude Opus 4.5: 68.1 (#28)
- Grok 4.20 (Non-Reasoning): 65.7 (#44)

| Benchmark | Claude Opus 4.5 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Text | 1451 | 1451 |
| LMArena Creative Writing | 1445 | 1438 |
| EQ-Bench Creative Writing | 1687 | 1574 |
| LMArena Multi-Turn | 1466 | 1456 |

## FAQ

### Is Claude Opus 4.5 better than Grok 4.20 (Non-Reasoning)?

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 48.6 on the Noometry Index. Grok 4.20 (Non-Reasoning) costs 6.4× less per token, which makes it the better buy when Claude Opus 4.5's lead doesn't matter for your workload.

### Which is cheaper, Claude Opus 4.5 or Grok 4.20 (Non-Reasoning)?

Grok 4.20 (Non-Reasoning) is cheaper. It lists at $1.25 per million input tokens and $2.50 per million output tokens; Claude Opus 4.5 lists at $5 and $25.

### Is Claude Opus 4.5 or Grok 4.20 (Non-Reasoning) better for coding?

Claude Opus 4.5 scores higher on coding benchmarks: 54.8 versus 42.1 in the Noometry coding category.

### Which has the bigger context window?

Grok 4.20 (Non-Reasoning) does, with 1M tokens against 200K.

### How many benchmarks do Claude Opus 4.5 and Grok 4.20 (Non-Reasoning) share?

42 benchmarks have published results for both models. Claude Opus 4.5 has 69 scored results on Noometry and Grok 4.20 (Non-Reasoning) has 46.