# Claude Sonnet 5.5 vs Kimi K3.1 Pro

> Side-by-side benchmark comparison for Claude Sonnet 5.5 and Kimi K3.1 Pro across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-sonnet-5-5-vs-kimi-3-1-pro
- Last updated: October 23, 2026

- Shared sourced benchmarks: 9
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Pick Claude Sonnet 5.5 if you want the stronger benchmark profile. Kimi K3.1 Pro only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Claude Sonnet 5.5 leads overall 82.2 to 82.
- The clearest category separation is in multimodal & grounded, where the averages are 85.1 for Claude Sonnet 5.5 and 98 for Kimi K3.1 Pro.
- The biggest single benchmark swing is Terminal-Bench-Science 0.1 in Agentic, with scores of 59.9% and 38.1%.
- Kimi K3.1 Pro also has the larger context window at 1.05M.

## Model Snapshot

| Property | Claude Sonnet 5.5 | Kimi K3.1 Pro |
|----------|----------|----------|
| Creator | Anthropic | Moonshot AI |
| Type | Proprietary | Pending |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1.05M |
| Overall Score | 82.2 | null |
| Benchmarks Covered | 56 | 42 |
| Pricing (input/output) | $2.00 / $10.00 | $2.00 / $10.00 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- Claude Sonnet 5.5 public-lane score: 69.2 (Supported · #11/132)
- Kimi K3.1 Pro public-lane score: Coming soon

| Benchmark | Claude Sonnet 5.5 | Kimi K3.1 Pro | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 4.0 | 70.60% | 65.70% | Claude Sonnet 5.5 |
| HLE w/ tools | 64.5% | 70.0% | Kimi K3.1 Pro |
| DRACO | 87.0% | Coming soon | Coming soon |
| Terminal-Bench-Science 0.1 | 59.9% | 38.1% | Claude Sonnet 5.5 |
| LAB all-pass (Harvey held-out) | 10.0% | Coming soon | Coming soon |
| LAB criterion-pass (Harvey held-out) | 93.1% | Coming soon | Coming soon |
| Toolathlon Verified Pass@3 | 85.2% | Coming soon | Coming soon |
| Toolathlon Verified Pass³ | 68.5% | Coming soon | Coming soon |
| Toolathlon Verified avg. turns | 31.6 turns | Coming soon | Coming soon |
| AutomationBench (Zapier 1.0.6) | 44.70% | Coming soon | Coming soon |
| Toolathlon-Verified | 77.8% | Coming soon | Coming soon |
| Hermes Index | 53.1% | Coming soon | Coming soon |
| Hermes Bench | 73.5% | Coming soon | Coming soon |
| MazeBench | 8% | Coming soon | Coming soon |
| BrowseComp | Coming soon | 92.1% | Coming soon |
| BioMysteryBench | Coming soon | 80.6% | Coming soon |
| Agents' Last Exam | Coming soon | 43.2% | Coming soon |
| Agents' Last Exam (CLI) | Coming soon | 44.2% | Coming soon |
| APEX-Agents | Coming soon | 67.2% | Coming soon |
| Frontier Finance | Coming soon | 58.6% | Coming soon |
| HANDBOOK.md | Coming soon | 44.6% | Coming soon |
| OSWorld 2.0 | Coming soon | 79.6% | Coming soon |
| Business Operation | Coming soon | 37.8% | Coming soon |
| Financial Modeling | Coming soon | 57.6% | Coming soon |
| Financial Research | Coming soon | 70.4% | Coming soon |
| Kimi Hallu Bench Hard (tools) | Coming soon | 8.3% | Coming soon |
| ExploitGym | Coming soon | 20.7% | Coming soon |

### Coding

- Winner: Not comparable
- Claude Sonnet 5.5 public-lane score: 84.3 (Supported · #1/153)
- Kimi K3.1 Pro public-lane score: Coming soon

| Benchmark | Claude Sonnet 5.5 | Kimi K3.1 Pro | Winner |
|-----------|-----------|-----------|--------|
| FrontierCode 1.1 Main | 46.2% | Coming soon | Coming soon |
| CursorBench 4.0 | 55.5% | Coming soon | Coming soon |
| SWE-bench Pro | 81.3% | Coming soon | Coming soon |
| SWE Multilingual | 90.3% | Coming soon | Coming soon |
| SWE Multimodal | 54.3% | Coming soon | Coming soon |
| DeepSWE | 71.0% | 75.5% | Kimi K3.1 Pro |
| FrontierCode 1.1 Extended | 59.1% | Coming soon | Coming soon |
| ProgramBench | 79.7% | Coming soon | Coming soon |
| FrontierSWE v2 | 61.9% | Coming soon | Coming soon |
| Bug Hunt Bench | 51.3 fixes | Coming soon | Coming soon |
| ProgramBench (binary) | Coming soon | 31.5% | Coming soon |
| Kimi Code Bench v2 | Coming soon | 77.1% | Coming soon |
| Kimi Code Bench 3.0 Long-horizon | Coming soon | 61.2% | Coming soon |
| sweMarathon | Coming soon | 51.7% | Coming soon |
| PostTrainBench v1.2 | Coming soon | 36.5% | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Sonnet 5.5 public-lane score: 81.8 (#6/27)
- Kimi K3.1 Pro public-lane score: Coming soon

### Multimodal & Grounded

- Winner: Not comparable
- Claude Sonnet 5.5 public-lane score: 85.1 (Unranked · 7 rankable rows)
- Kimi K3.1 Pro public-lane score: 98 (#1/56)

| Benchmark | Claude Sonnet 5.5 | Kimi K3.1 Pro | Winner |
|-----------|-----------|-----------|--------|
| ExtractBench Pro | 32% | Coming soon | Coming soon |
| ExtractBench (LlamaIndex) | 94.68% | Coming soon | Coming soon |
| ParseBench | 70.18% | Coming soon | Coming soon |
| Chartography (no tools) | 61.6% | Coming soon | Coming soon |
| Chartography (tools) | 90.2% | 90.2% | Tie |
| BenchCAD Vision2Code (no tools) | 0.747 | 0.728 | Claude Sonnet 5.5 |
| BenchCAD Vision2Code (tools) | 0.963 | 0.927 | Claude Sonnet 5.5 |
| Biomedical image analysis | 72.2% | Coming soon | Coming soon |
| OfficeQA | 76.9% | Coming soon | Coming soon |
| OfficeQA Pro | 65.6% | 67.4% | Kimi K3.1 Pro |
| OfficeQA Pro v2 | Coming soon | 64.4% | Coming soon |
| MMMU-Pro | Coming soon | 84.1% | Coming soon |
| MMMU-Pro w/ Python | Coming soon | 90% | Coming soon |
| CharXiv | Coming soon | 93.4% | Coming soon |
| CharXiv w/o tools | Coming soon | 89% | Coming soon |
| BabyVision w/ Python | Coming soon | 95.4% | Coming soon |
| ZeroBench | Coming soon | 39.0% | Coming soon |
| ZeroBench w/ Python | Coming soon | 63.0% | Coming soon |
| GDP.pdf (Gemini judge) | Coming soon | 34.6% | Coming soon |
| GDP.pdf w/ Python (Gemini judge) | Coming soon | 85.7% | Coming soon |
| PerceptionBench | Coming soon | 68.3% | Coming soon |

### Knowledge

- Winner: Not comparable
- Claude Sonnet 5.5 public-lane score: 82.3 (Supported · #5/187)
- Kimi K3.1 Pro public-lane score: Coming soon

| Benchmark | Claude Sonnet 5.5 | Kimi K3.1 Pro | Winner |
|-----------|-----------|-----------|--------|
| HealthBench (raw) | 69.4% | Coming soon | Coming soon |
| HealthBench (length-adjusted) | 65.4% | Coming soon | Coming soon |
| HealthBench Professional (raw) | 77.1% | Coming soon | Coming soon |
| HealthBench Professional | 69.2% | Coming soon | Coming soon |
| BioMysteryBench (human-solvable) | 89.2% | Coming soon | Coming soon |
| BioMysteryBench (human-difficult) | 44.7% | Coming soon | Coming soon |
| SpatialBench Verified | 72.5% | Coming soon | Coming soon |
| SingleCellBench | 59.1% | Coming soon | Coming soon |
| Protein Design | 51.0% | Coming soon | Coming soon |
| Morphology-to-molecule matching | 25.0% | Coming soon | Coming soon |
| Medicinal chemistry | 65.3% | Coming soon | Coming soon |
| Protein Design library ranking | 54.8% | Coming soon | Coming soon |
| De novo protein-binder design | 82.3% | Coming soon | Coming soon |
| Protocols (troubleshooting) | 67.3% | Coming soon | Coming soon |
| Protocols (understanding) | 66.6% | Coming soon | Coming soon |
| HLE w/o tools | 56.9% | 51.1% | Claude Sonnet 5.5 |
| GPQA | Coming soon | 94.2% | Coming soon |
| GPQA-D | Coming soon | 94.2% | Coming soon |
| HLE | Coming soon | 70% | Coming soon |
| Kimi Hallu Bench | Coming soon | 5.4% | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude Sonnet 5.5 public-lane score: Coming soon
- Kimi K3.1 Pro public-lane score: Coming soon

| Benchmark | Claude Sonnet 5.5 | Kimi K3.1 Pro | Winner |
|-----------|-----------|-----------|--------|
| GMMLU | 92.1% | Coming soon | Coming soon |
| MILU | 91.6% | Coming soon | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude Sonnet 5.5 public-lane score: 95.2 (Unranked · 4 rankable rows)
- Kimi K3.1 Pro public-lane score: Coming soon

| Benchmark | Claude Sonnet 5.5 | Kimi K3.1 Pro | Winner |
|-----------|-----------|-----------|--------|
| ArXivMath Aug. 2026 (no tools) | 86.8% | Coming soon | Coming soon |
| ArXivMath Aug. 2026 (tools) | 95.2% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 88.772% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 80.488% | Coming soon | Coming soon |

## FAQ

### Which is better overall, Claude Sonnet 5.5 or Kimi K3.1 Pro?

Claude Sonnet 5.5 is ahead overall on BenchLM right now.

### Where is the biggest gap between Claude Sonnet 5.5 and Kimi K3.1 Pro?

The widest category gap is in multimodal & grounded, where the averages are 85.1 for Claude Sonnet 5.5 and 98 for Kimi K3.1 Pro.

### How many benchmarks does Claude Sonnet 5.5 cover on BenchLM?

Claude Sonnet 5.5 currently has 56 sourced benchmark scores on BenchLM.

### How many benchmarks does Kimi K3.1 Pro cover on BenchLM?

Kimi K3.1 Pro currently has 42 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Sonnet 5.5 vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-claude-sonnet-5-5)
- [Kimi K3.1 Pro vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-kimi-3-1-pro)
- [Claude Sonnet 5.5 vs GPT-6.1 Sol](/compare/claude-sonnet-5-5-vs-gpt-6-1-sol)
- [Kimi K3.1 Pro vs GPT-6.1 Sol](/compare/gpt-6-1-sol-vs-kimi-3-1-pro)

## Explore More

- [Claude Sonnet 5.5 profile](/models/claude-sonnet-5-5)
- [Kimi K3.1 Pro profile](/models/kimi-3-1-pro)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)