# Claude Sonnet 4.5 vs Kimi K2.5

> Side-by-side benchmark comparison for Claude Sonnet 4.5 and Kimi K2.5 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-sonnet-4-5-vs-kimi-k2-5
- Last updated: September 29, 2026

- Shared sourced benchmarks: 8
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.7

## Quick Verdict

Pick Kimi K2.5 if you want the stronger benchmark profile. Claude Sonnet 4.5 only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Kimi K2.5 leads overall 52.85 to 47.85.
- The clearest category separation is in reasoning, where the averages are 19.2 for Claude Sonnet 4.5 and 55.2 for Kimi K2.5.
- The biggest single benchmark swing is JobBench in Agentic, with scores of 27.7% and 8.7%.
- Kimi K2.5 is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- Kimi K2.5 also has the larger context window at 256K.

## Model Snapshot

| Property | Claude Sonnet 4.5 | Kimi K2.5 |
|----------|----------|----------|
| Creator | Anthropic | Moonshot AI |
| Type | Proprietary | Open Weight |
| Reasoning | Non-Reasoning | Non-Reasoning |
| Context | 200K | 256K |
| Overall Score | 47.85 | 52.85 |
| Benchmarks Covered | 11 | 45 |
| Pricing (input/output) | $3.00 / $15.00 | $0.60 / $3.00 |

## Category Breakdown

### Agentic

- Winner: Directional only
- Claude Sonnet 4.5 public-lane score: 34.6 (Estimated · #67/117)
- Kimi K2.5 public-lane score: 36.5 (Estimated · #61/117)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 50% | 50.8% | Kimi K2.5 |
| OSWorld-Verified | 61.4% | Coming soon | Coming soon |
| VITA-Bench | 17.0% | Coming soon | Coming soon |
| Gert Labs | 48.51% | 45.88% | Claude Sonnet 4.5 |
| JobBench | 27.7% | 8.7% | Claude Sonnet 4.5 |
| BrowseComp | Coming soon | 60.6% | Coming soon |
| Claw-Eval | Coming soon | 52.3% | Coming soon |
| QwenClawBench | Coming soon | 54.3% | Coming soon |
| τ³-bench results | Coming soon | 65.7% | Coming soon |
| DeepSearchQA | Coming soon | 77.1% | Coming soon |
| DeepPlanning | Coming soon | 14.4% | Coming soon |
| Toolathlon | Coming soon | 27.8% | Coming soon |
| MCP Atlas | Coming soon | 29.5% | Coming soon |
| MCP-Tasks | Coming soon | 59.1% | Coming soon |
| WideResearch | Coming soon | 72.7% | Coming soon |
| ResearchClawBench | Coming soon | 14.0% | Coming soon |

### Coding

- Winner: Not comparable
- Claude Sonnet 4.5 public-lane score: Coming soon
- Kimi K2.5 public-lane score: 38.8 (Estimated · #66/143)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 77.2% | 76.8% | Claude Sonnet 4.5 |
| SWE-bench Verified* | Coming soon | 70.8% | Coming soon |
| LiveCodeBench v6 | Coming soon | 85.0% | Coming soon |
| SWE-bench Pro | Coming soon | 50.7% | Coming soon |
| SWE Multilingual | Coming soon | 73% | Coming soon |
| SWE-Rebench | Coming soon | 58.5% | Coming soon |
| React Native Evals | Coming soon | 77.2% | Coming soon |
| SciCode | Coming soon | 48.7% | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Sonnet 4.5 public-lane score: 19.2 (Unranked · 1 rankable row)
- Kimi K2.5 public-lane score: 55.2 (Unranked · 3 rankable rows)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | 13.6% | Coming soon | Coming soon |
| LongBench v2 | Coming soon | 61% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Claude Sonnet 4.5 public-lane score: Coming soon
- Kimi K2.5 public-lane score: 66.8 (#25/50)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | Coming soon | 78.5% | Coming soon |
| Video-MME | Coming soon | 87.4% | Coming soon |
| MMVU | Coming soon | 80.4% | Coming soon |
| VideoMMMU | Coming soon | 86.6% | Coming soon |

### Knowledge

- Winner: Not comparable
- Claude Sonnet 4.5 public-lane score: Coming soon
- Kimi K2.5 public-lane score: 47.8 (Estimated · #71/169)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 83.4% | 87.6% | Kimi K2.5 |
| GPQA-D | Coming soon | 87.6% | Coming soon |
| SuperGPQA | Coming soon | 69.2% | Coming soon |
| MMLU-Pro | Coming soon | 87.1% | Coming soon |
| MMLU-Pro (Arcee) | Coming soon | 87.1% | Coming soon |
| HLE | Coming soon | 30.1% | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude Sonnet 4.5 public-lane score: Coming soon
- Kimi K2.5 public-lane score: 38.2 (#8/12)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| MMLU-ProX | Coming soon | 82.3% | Coming soon |
| NOVA-63 | Coming soon | 56.0% | Coming soon |

### Instruction Following

- Winner: Not comparable
- Claude Sonnet 4.5 public-lane score: Coming soon
- Kimi K2.5 public-lane score: 84.4 (#41/124)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 93.9% | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude Sonnet 4.5 public-lane score: 34.6 (Unranked · 2 rankable rows)
- Kimi K2.5 public-lane score: 62.1 (#4/7)

| Benchmark | Claude Sonnet 4.5 | Kimi K2.5 | Winner |
|-----------|-----------|-----------|--------|
| AIME 2025 | 87% | 96.1% | Kimi K2.5 |
| FrontierMath v2 (Tiers 1-3) | 13.495% | 27.900% | Kimi K2.5 |
| FrontierMath v2 (Tier 4) | 4.167% | 4.200% | Kimi K2.5 |
| AIME26 | Coming soon | 95.8% | Coming soon |
| AIME25 (Arcee) | Coming soon | 96.3% | Coming soon |
| HMMT Feb 2025 | Coming soon | 95.4% | Coming soon |
| HMMT Nov 2025 | Coming soon | 91.1% | Coming soon |
| HMMT Feb 2026 | Coming soon | 87.1% | Coming soon |
| MMAnswerBench | Coming soon | 81.8% | Coming soon |

## FAQ

### Which is better overall, Claude Sonnet 4.5 or Kimi K2.5?

Kimi K2.5 is ahead overall on BenchLM right now.

### Where is the biggest gap between Claude Sonnet 4.5 and Kimi K2.5?

The widest category gap is in reasoning, where the averages are 19.2 for Claude Sonnet 4.5 and 55.2 for Kimi K2.5.

### How many benchmarks does Claude Sonnet 4.5 cover on BenchLM?

Claude Sonnet 4.5 currently has 11 sourced benchmark scores on BenchLM.

### How many benchmarks does Kimi K2.5 cover on BenchLM?

Kimi K2.5 currently has 45 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Sonnet 4.5 vs Claude Sonnet 4.5 Thinking](/compare/claude-sonnet-4-5-vs-claude-sonnet-4-5-thinking)
- [Kimi K2.5 vs Claude Sonnet 4.5 Thinking](/compare/claude-sonnet-4-5-thinking-vs-kimi-k2-5)
- [Claude Sonnet 4.5 vs Kimi K2.5 (Reasoning)](/compare/claude-sonnet-4-5-vs-kimi-k2-5-reasoning)
- [Kimi K2.5 vs Kimi K2.5 (Reasoning)](/compare/kimi-k2-5-vs-kimi-k2-5-reasoning)

## Explore More

- [Claude Sonnet 4.5 profile](/models/claude-sonnet-4-5)
- [Kimi K2.5 profile](/models/kimi-k2-5)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)