# Claude Opus 4.5 vs Sakana Fugu-Ultra

> Side-by-side benchmark comparison for Claude Opus 4.5 and Sakana Fugu-Ultra across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-opus-4-5-vs-sakana-fugu-ultra
- Last updated: September 28, 2026

- Shared sourced benchmarks: 4
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.7

## Quick Verdict

Pick Sakana Fugu-Ultra if you want the stronger benchmark profile. Claude Opus 4.5 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 74 to 55.03.
- The clearest category separation is in multimodal & grounded, where the averages are 24.5 for Claude Opus 4.5 and 73.6 for Sakana Fugu-Ultra.
- The biggest single benchmark swing is CharXiv in Multimodal & Grounded, with scores of 68.5% and 86.6%.
- Sakana Fugu-Ultra is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- Sakana Fugu-Ultra also has the larger context window at 1M.

## Model Snapshot

| Property | Claude Opus 4.5 | Sakana Fugu-Ultra |
|----------|----------|----------|
| Creator | Anthropic | Sakana AI |
| Type | Proprietary | Proprietary |
| Reasoning | Non-Reasoning | Reasoning |
| Context | 200K | 1M |
| Overall Score | 55.03 | null |
| Benchmarks Covered | 45 | 11 |
| Pricing (input/output) | $5.00 / $25.00 | Pricing unavailable / Pricing unavailable |

## Category Breakdown

### Agentic

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 31.1 (Estimated · #78/117)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 59.3% | Coming soon | Coming soon |
| OSWorld-Verified | 66.3% | Coming soon | Coming soon |
| OSWorld | 66.3% | Coming soon | Coming soon |
| Claw-Eval | 59.6% | Coming soon | Coming soon |
| QwenClawBench | 52.3% | Coming soon | Coming soon |
| τ³-bench results | 70.2% | Coming soon | Coming soon |
| VITA-Bench | 23.3% | Coming soon | Coming soon |
| DeepPlanning | 26.4% | Coming soon | Coming soon |
| Toolathlon | 43.5% | Coming soon | Coming soon |
| MCP Atlas | 42.3% | Coming soon | Coming soon |
| MCP-Tasks | 71.8% | Coming soon | Coming soon |
| WideResearch | 76.4% | Coming soon | Coming soon |
| CyberGym | 50.6% | Coming soon | Coming soon |
| Gert Labs | 64.23% | Coming soon | Coming soon |
| JobBench | 32.3% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 82.1% | Coming soon |

### Coding

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 42.3 (Estimated · #56/142)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 80.9% | Coming soon | Coming soon |
| LiveCodeBench v6 | 84.8% | 93.2% | Sakana Fugu-Ultra |
| SWE-bench Pro | 57.1% | 73.7% | Sakana Fugu-Ultra |
| SWE Multilingual | 77.5% | Coming soon | Coming soon |
| NL2Repo | 43.2% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | Coming soon | 82.1% | Coming soon |
| LiveCodeBench Pro | Coming soon | 90.8% | Coming soon |
| SciCode | Coming soon | 58.7% | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 73.3 (Unranked · 4 rankable rows)
- Sakana Fugu-Ultra public-lane score: 79.1 (Unranked · 1 rankable row)

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| LongBench v2 | 64.4% | Coming soon | Coming soon |
| AI-Needle | 74% | Coming soon | Coming soon |
| MRCRv2 | Coming soon | 93.6% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 24.5 (#48/50)
- Sakana Fugu-Ultra public-lane score: 73.6 (Unranked · 1 rankable row)

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | 70.6% | Coming soon | Coming soon |
| MathVision | 74.3% | Coming soon | Coming soon |
| CharXiv | 68.5% | 86.6% | Sakana Fugu-Ultra |
| VideoMMMU | 84.4% | Coming soon | Coming soon |
| ScreenSpot Pro | 45.7% | Coming soon | Coming soon |
| V* | 67.0% | Coming soon | Coming soon |

### Knowledge

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 49.5 (Estimated · #61/168)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 87% | 95.5% | Sakana Fugu-Ultra |
| SuperGPQA | 70.6% | Coming soon | Coming soon |
| MMLU-Pro | 89.5% | Coming soon | Coming soon |
| MMLU-Redux | 96.6% | Coming soon | Coming soon |
| C-Eval | 92.2% | Coming soon | Coming soon |
| HLE | 30.8% | Coming soon | Coming soon |
| GPQA-D | Coming soon | 95.5% | Coming soon |
| HLE w/o tools | Coming soon | 50% | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 82.9 (#2/12)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| MMLU-ProX | 85.7% | Coming soon | Coming soon |
| NOVA-63 | 56.7% | Coming soon | Coming soon |

### Instruction Following

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 30.6 (#114/124)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| IFEval | 90.9% | Coming soon | Coming soon |
| IFBench | 58% | Coming soon | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude Opus 4.5 public-lane score: 57.9 (#6/7)
- Sakana Fugu-Ultra public-lane score: Coming soon

| Benchmark | Claude Opus 4.5 | Sakana Fugu-Ultra | Winner |
|-----------|-----------|-----------|--------|
| AIME26 | 95.1% | Coming soon | Coming soon |
| HMMT Feb 2025 | 92.9% | Coming soon | Coming soon |
| HMMT Nov 2025 | 93.3% | Coming soon | Coming soon |
| HMMT Feb 2026 | 85.3% | Coming soon | Coming soon |
| MMAnswerBench | 84.0% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 20.690% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 4.167% | Coming soon | Coming soon |

## FAQ

### Which is better overall, Claude Opus 4.5 or Sakana Fugu-Ultra?

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

### Where is the biggest gap between Claude Opus 4.5 and Sakana Fugu-Ultra?

The widest category gap is in multimodal & grounded, where the averages are 24.5 for Claude Opus 4.5 and 73.6 for Sakana Fugu-Ultra.

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

Claude Opus 4.5 currently has 45 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 Opus 4.5 vs Claude Opus 4.5 Thinking](/compare/claude-opus-4-5-vs-claude-opus-4-5-thinking)
- [Sakana Fugu-Ultra vs Claude Opus 4.5 Thinking](/compare/claude-opus-4-5-thinking-vs-sakana-fugu-ultra)
- [Claude Opus 4.5 vs Sakana Fugu](/compare/claude-opus-4-5-vs-sakana-fugu)
- [Sakana Fugu-Ultra vs Sakana Fugu](/compare/sakana-fugu-vs-sakana-fugu-ultra)

## Explore More

- [Claude Opus 4.5 profile](/models/claude-opus-4-5)
- [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)