# Claude Sonnet 4.5 vs Grok 4.3

> Claude Sonnet 4.5 and Grok 4.3 score almost the same on the Noometry Index (44.0 vs 43.6), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/claude-sonnet-4-5-vs-grok-4-3
- Last updated: 2026-10-10
- Shared benchmarks: 36

## Summary

- They share 36 benchmarks with published results for both. Claude Sonnet 4.5 scores higher in 7 categories and Grok 4.3 in 3 categories; 10 gaps are clear of the uncertainty.
- The widest gap is in math, where Grok 4.3 leads 45.8 to 31.9.
- The biggest single-benchmark swing is FrontierMath (Tiers 1-3): 23.9% for Claude Sonnet 4.5 and 42.8% for Grok 4.3.
- Grok 4.3 is cheaper at $1.25 / $2.50 per million input/output tokens, against $3 / $15 for Claude Sonnet 4.5.

## Snapshot

| | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| Provider | Anthropic | xAI |
| Noometry Index | 44.0 | 43.6 |
| Rank | 76 | 80 |
| Context | 1M | 1M |
| Input $/M | $3 | $1.25 |
| Output $/M | $15 | $2.50 |
| Weights | Proprietary | Proprietary |

## Coding

- Claude Sonnet 4.5: 47.8 (#54)
- Grok 4.3: 41.3 (#117)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| LMArena WebDev | 1393 | 1357 |
| SciCode | 44.7% | 47.3% |
| WeirdML | 47.7% | 49.9% |
| LMArena Coding | 1489 | 1415 |
| ALE-Bench | 796.15 | 944.17 |
| SWE-bench Verified | 71.3% | — |
| SWE-bench Verified (bash only) | 71.4% | — |
| SWE-bench Multilingual | 67% | — |
| GSO | 14.7% | — |
| AlgoTune | 1.52 | — |

## Agentic & Tool Use

- Claude Sonnet 4.5: 38.1 (#30)
- Grok 4.3: 27.6 (#93)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| LMArena Search | 1159 | 1165 |
| Vending-Bench 2 | 3,839 | 35.26 |
| Terminal-Bench | 46.5% | — |
| Berkeley Function Calling Leaderboard | 73.2% | — |
| GDPval | 42.5% | — |
| Remote Labor Index | 2.1% | — |
| τ²-bench Airline | 72% | — |
| τ²-bench Banking | 25.3% | — |
| τ²-bench Retail | 72.4% | — |
| τ²-bench Telecom | 84.9% | — |
| Cybench | 60% | — |
| DeepResearch Bench | 52.6% | — |
| OSWorld | 62.9% | — |
| GDP.pdf | — | 8% |
| METR Time Horizons | 67.4% | — |

## Reasoning

- Claude Sonnet 4.5: 26.9 (#113)
- Grok 4.3: 34.9 (#60)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| NYT Connections (extended) | 37.3% | 55.2% |
| CritPt | 1.1% | 8% |
| Chess Puzzles | 12% | 25% |
| LMArena Hard Prompts | 1462 | 1397 |
| DTBench | 83.2% | 90.7% |
| LMCA | 38.8% | 38.3% |
| Epoch Capabilities Index | 146.84 | 149.13 |
| ForecastBench | 61.9 | 60.3 |
| ARC-AGI-2 | 13.6% | — |
| SimpleBench | 54.3% | — |
| Kagi LLM Benchmark | 57.9% | — |
| ARC-AGI-1 | 63.7% | — |
| EnigmaEval | 6% | — |
| EBR-Bench | 2.4% | — |
| Mystery Game Puzzles | 17% | — |

## Math

- Claude Sonnet 4.5: 31.9 (#190)
- Grok 4.3: 45.8 (#60)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 23.9% | 42.8% |
| FrontierMath Tier 4 | 2.4% | 14.6% |
| OTIS Mock AIME 2024-2025 | 77.8% | 93.3% |
| ProofBench | 19% | 11% |
| LMArena Math | 1448 | 1388 |
| Omni-MATH | 55.3% | — |
| MATH Level 5 | 97.7% | — |
| FrontierMath (Feb 2025 set) | 15.2% | — |
| FrontierMath Tier 4 (v1) | 4.2% | — |

## Knowledge

- Claude Sonnet 4.5: 48.4 (#70)
- Grok 4.3: 52.5 (#57)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| GPQA Diamond | 82.3% | 88.8% |
| SimpleQA Verified | 30.7% | 33.2% |
| LMArena Expert | 1483 | 1385 |
| Humanity's Last Exam | 13.7% | — |
| MMLU-Pro | 86.9% | — |
| Vectara Hallucination Rate | 12% | — |
| GPQA (HELM) | 68.6% | — |

## Multimodal

- Claude Sonnet 4.5: 34.1 (#84)
- Grok 4.3: 31.6 (#96)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| LMArena Vision | — | 1231 |
| VPCT | 39.8% | — |
| Blueprint-Bench 2 | — | 0% |
| LMArena Document | 1450 | — |

## Multilingual

- Claude Sonnet 4.5: 53.6 (#65)
- Grok 4.3: 50.7 (#114)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| LMArena Non-English | 1425 | 1385 |
| LMArena Chinese | 1459 | 1423 |
| LMArena French | 1459 | 1412 |
| LMArena German | 1427 | 1395 |
| LMArena Japanese | 1390 | 1379 |
| LMArena Korean | 1403 | 1357 |
| LMArena Russian | 1436 | 1399 |
| LMArena Spanish | 1457 | 1402 |

## Instruction Following

- Claude Sonnet 4.5: 75.2 (#74)
- Grok 4.3: 72.3 (#135)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| LMArena Instruction Following | 1459 | 1366 |
| IFEval | 85% | — |

## Long Context

- Claude Sonnet 4.5: 45.2 (#45)
- Grok 4.3: 42.5 (#118)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| LMArena Longer Query | 1476 | 1393 |

## Writing & Preference

- Claude Sonnet 4.5: 66.7 (#33)
- Grok 4.3: 58.6 (#112)

| Benchmark | Claude Sonnet 4.5 | Grok 4.3 |
|---|---|---|
| LMArena Text | 1439 | 1397 |
| LMArena Creative Writing | 1442 | 1380 |
| LMArena Multi-Turn | 1465 | 1406 |
| EQ-Bench Creative Writing | 1678 | — |
| WildBench | 85.4% | — |
| EQ-Bench 4 | — | 1075 |

## FAQ

### Is Claude Sonnet 4.5 better than Grok 4.3?

Claude Sonnet 4.5 and Grok 4.3 score almost the same on the Noometry Index (44.0 vs 43.6), so choose on price, context window or the category you care about most.

### Which is cheaper, Claude Sonnet 4.5 or Grok 4.3?

Grok 4.3 is cheaper. It lists at $1.25 per million input tokens and $2.50 per million output tokens; Claude Sonnet 4.5 lists at $3 and $15.

### Is Claude Sonnet 4.5 or Grok 4.3 better for coding?

Claude Sonnet 4.5 scores higher on coding benchmarks: 47.8 versus 41.3 in the Noometry coding category.

### Which has the bigger context window?

Both accept 1M tokens.

### How many benchmarks do Claude Sonnet 4.5 and Grok 4.3 share?

36 benchmarks have published results for both models. Claude Sonnet 4.5 has 73 scored results on Noometry and Grok 4.3 has 40.