# Claude Sonnet 5 vs Grok 4.3

> Side-by-side benchmark comparison for Claude Sonnet 5 and Grok 4.3 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-sonnet-5-vs-grok-4-3
- Last updated: September 29, 2026

- Shared sourced benchmarks: 5
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.7

## Quick Verdict

Pick Claude Sonnet 5 if you want the stronger benchmark profile. Grok 4.3 only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Claude Sonnet 5 leads overall 66.99 to 54.68.
- The clearest category separation is in agentic, where the averages are 64.6 for Claude Sonnet 5 and 25.8 for Grok 4.3.
- The biggest single benchmark swing is Terminal-Bench 2.1 (Vals) in Agentic, with scores of 74.5% and 41.9%.
- Grok 4.3 is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.

## Model Snapshot

| Property | Claude Sonnet 5 | Grok 4.3 |
|----------|----------|----------|
| Creator | Anthropic | xAI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Overall Score | 66.99 | 54.68 |
| Benchmarks Covered | 26 | 7 |
| Pricing (input/output) | $2.00 / $10.00 | $1.25 / $2.50 |

## Category Breakdown

### Agentic

- Winner: Claude Sonnet 5
- Claude Sonnet 5 public-lane score: 64.6 (Supported · #12/117)
- Grok 4.3 public-lane score: 25.8 (Supported · #89/117)

| Benchmark | Claude Sonnet 5 | Grok 4.3 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 3.0 | 14.6% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 80.4% | Coming soon | Coming soon |
| BrowseComp | 84.7% | Coming soon | Coming soon |
| HLE w/ tools | 57.4% | Coming soon | Coming soon |
| OSWorld-Verified | 81.2% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 74.5% | 41.9% | Claude Sonnet 5 |
| ApprenticeBench | 16% | Coming soon | Coming soon |
| Gert Labs | Coming soon | 43.86% | Coming soon |
| ResearchClawBench | Coming soon | 12.4% | Coming soon |

### Coding

- Winner: Claude Sonnet 5
- Claude Sonnet 5 public-lane score: 59.8 (Supported · #19/142)
- Grok 4.3 public-lane score: 29.4 (Supported · #94/142)

| Benchmark | Claude Sonnet 5 | Grok 4.3 | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 85.2% | Coming soon | Coming soon |
| SWE-bench Pro | 63.2% | Coming soon | Coming soon |
| SWE Multilingual | 78.3% | Coming soon | Coming soon |
| SWE Multimodal | 28.1% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 80.4% | Coming soon | Coming soon |
| FrontierCode 1.1 Main | 42.7% | Coming soon | Coming soon |
| cursorBench32 | 61.5% | Coming soon | Coming soon |
| VulcanBench CII v1 | 89.2% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 82.4% | 84.5% | Grok 4.3 |
| SWE-bench (Vals) | 79.6% | 71.4% | Claude Sonnet 5 |
| cursorBench40 | 34.1% | Coming soon | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Sonnet 5 public-lane score: 78.7 (Unranked · 2 rankable rows)
- Grok 4.3 public-lane score: 66.5 (Unranked · 2 rankable rows)

### Multimodal & Grounded

- Winner: Directional only
- Claude Sonnet 5 public-lane score: 78.4 (#15/50)
- Grok 4.3 public-lane score: 66.7 (#26/50)

| Benchmark | Claude Sonnet 5 | Grok 4.3 | Winner |
|-----------|-----------|-----------|--------|
| CharXiv | 88.3% | Coming soon | Coming soon |
| CharXiv w/o tools | 77% | Coming soon | Coming soon |

### Knowledge

- Winner: Claude Sonnet 5
- Claude Sonnet 5 public-lane score: 64.5 (Supported · #26/168)
- Grok 4.3 public-lane score: 53.5 (Supported · #51/168)

| Benchmark | Claude Sonnet 5 | Grok 4.3 | Winner |
|-----------|-----------|-----------|--------|
| HLE | 57.4% | Coming soon | Coming soon |
| HLE w/o tools | 43.2% | Coming soon | Coming soon |
| HLE-Verified | 31.0% | Coming soon | Coming soon |
| LABBench2 | 80.1% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 88.9% | 91.4% | Grok 4.3 |
| MMLU-Pro (Vals) | 87.5% | 85.8% | Claude Sonnet 5 |

### Instruction Following

- Winner: Not comparable
- Claude Sonnet 5 public-lane score: Coming soon
- Grok 4.3 public-lane score: 93.2 (#2/124)

## FAQ

### Which is better overall, Claude Sonnet 5 or Grok 4.3?

Claude Sonnet 5 is ahead overall on BenchLM right now.

### Where is the biggest gap between Claude Sonnet 5 and Grok 4.3?

The widest category gap is in agentic, where the averages are 64.6 for Claude Sonnet 5 and 25.8 for Grok 4.3.

### How many benchmarks does Claude Sonnet 5 cover on BenchLM?

Claude Sonnet 5 currently has 26 sourced benchmark scores on BenchLM.

### How many benchmarks does Grok 4.3 cover on BenchLM?

Grok 4.3 currently has 7 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Sonnet 5 vs GPT-6 Astra](/compare/claude-sonnet-5-vs-gpt-6-astra)
- [Grok 4.3 vs GPT-6 Astra](/compare/gpt-6-astra-vs-grok-4-3)
- [Claude Sonnet 5 vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-claude-sonnet-5)
- [Grok 4.3 vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-grok-4-3)

## Explore More

- [Claude Sonnet 5 profile](/models/claude-sonnet-5)
- [Grok 4.3 profile](/models/grok-4-3)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)