# Claude Sonnet 5 vs Sakana Fugu-Ultra

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

- Canonical page: https://benchlm.ai/compare/claude-sonnet-5-vs-sakana-fugu-ultra
- Last updated: September 18, 2026

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

## Quick Verdict

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

## Summary

- Sakana Fugu-Ultra leads overall 76 to 69.68.
- The clearest category separation is in multimodal & grounded, where the averages are 77.4 for Claude Sonnet 5 and 72.6 for Sakana Fugu-Ultra.
- The biggest single benchmark swing is SWE-bench Pro in Coding, with scores of 63.2% and 73.7%.
- Sakana Fugu-Ultra is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.

## Model Snapshot

| Property | Claude Sonnet 5 | Sakana Fugu-Ultra |
|----------|----------|----------|
| Creator | Anthropic | Sakana AI |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Overall Score | 69.68 | null |
| Benchmarks Covered | 26 | 11 |
| Pricing (input/output) | $2.00 / $10.00 | Pricing unavailable / Pricing unavailable |

## Category Breakdown

### Agentic

- Winner: Coming soon
- Claude Sonnet 5 public-lane score: 65.9 (Supported · #11/154)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Sonnet 5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 3.0 | 14.6% | Coming soon | Coming soon |
| Terminal-Bench 2.0 | 80.4% | 82.1% | Sakana Fugu-Ultra |
| 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% | Coming soon | Coming soon |
| ApprenticeBench | 16% | Coming soon | Coming soon |

### Coding

- Winner: Coming soon
- Claude Sonnet 5 public-lane score: 63.9 (Supported · #13/154)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Sonnet 5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 85.2% | Coming soon | Coming soon |
| SWE-bench Pro | 63.2% | 73.7% | Sakana Fugu-Ultra |
| SWE Multilingual | 78.3% | Coming soon | Coming soon |
| SWE Multimodal | 28.1% | Coming soon | Coming soon |
| Terminal-Bench 2.0 | 80.4% | 82.1% | Sakana Fugu-Ultra |
| 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% | Coming soon | Coming soon |
| SWE-bench (Vals) | 79.6% | Coming soon | Coming soon |
| cursorBench40 | 34.1% | Coming soon | Coming soon |
| LiveCodeBench v6 | Coming soon | 93.2% | Coming soon |
| LiveCodeBench Pro | Coming soon | 90.8% | Coming soon |
| SciCode | Coming soon | 58.7% | Coming soon |

### Multimodal & Grounded

- Winner: Coming soon
- Claude Sonnet 5 public-lane score: 77.4 (#14/48)
- Sakana Fugu-Ultra public-lane score: 72.6 (Unranked · 1 rankable row)

| Benchmark | Claude Sonnet 5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| CharXiv | 88.3% | 86.6% | Claude Sonnet 5 |
| CharXiv w/o tools | 77% | Coming soon | Coming soon |

### Reasoning

- Winner: Coming soon
- Claude Sonnet 5 public-lane score: 77.4 (Unranked · 2 rankable rows)
- Sakana Fugu-Ultra public-lane score: 77.9 (Unranked · 1 rankable row)

| Benchmark | Claude Sonnet 5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| MRCRv2 | Coming soon | 93.6% | Coming soon |

### Knowledge

- Winner: Coming soon
- Claude Sonnet 5 public-lane score: 66.5 (Supported · #20/184)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Sonnet 5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| HLE | 57.4% | Coming soon | Coming soon |
| HLE w/o tools | 43.2% | 50% | Sakana Fugu-Ultra |
| HLE-Verified | 31.0% | Coming soon | Coming soon |
| LABBench2 | 80.1% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 88.9% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 87.5% | Coming soon | Coming soon |
| GPQA | Coming soon | 95.5% | Coming soon |
| GPQA-D | Coming soon | 95.5% | Coming soon |

## FAQ

### Which is better overall, Claude Sonnet 5 or Sakana Fugu-Ultra?

Sakana Fugu-Ultra is ahead overall on BenchLM right now.

### Where is the biggest gap between Claude Sonnet 5 and Sakana Fugu-Ultra?

The widest category gap is in multimodal & grounded, where the averages are 77.4 for Claude Sonnet 5 and 72.6 for Sakana Fugu-Ultra.

### 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 Sakana Fugu-Ultra cover on BenchLM?

Sakana Fugu-Ultra currently has 11 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Claude Sonnet 5 vs Sakana Fugu](/compare/claude-sonnet-5-vs-sakana-fugu)
- [Sakana Fugu-Ultra vs Sakana Fugu](/compare/sakana-fugu-vs-sakana-fugu-ultra)
- [Claude Sonnet 5 vs Fugu Cyber](/compare/claude-sonnet-5-vs-sakana-fugu-cyber)
- [Sakana Fugu-Ultra vs Fugu Cyber](/compare/sakana-fugu-cyber-vs-sakana-fugu-ultra)

## Explore More

- [Claude Sonnet 5 profile](/models/claude-sonnet-5)
- [Sakana Fugu-Ultra profile](/models/sakana-fugu-ultra)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)