Model comparison
Claude Opus 5 vs Sakana Fugu-Ultra
Head-to-head evidence from 2 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Opus 5 #1 (Estimated); Sakana Fugu-Ultra unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Opus 5 and Sakana Fugu-Ultra share 2 comparable benchmark results. 5 of 8 categories are comparable. 77 results are unique to Claude Opus 5; 9 to Sakana Fugu-Ultra.
Updated July 24, 2026- Shared results
- 2
- Claude Opus 5 only
- 77
- Sakana Fugu-Ultra only
- 9
- Comparable categories
- 5 / 8
Treat this as a split decision. Claude Opus 5 makes more sense if coding is the priority; Sakana Fugu-Ultra is the better fit if knowledge is the priority.
Confidence note. This is a partial-evidence comparison with 2 shared benchmark results across 2 evidence categories; 5 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Opus 5 and Sakana Fugu-Ultra finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Claude Opus 5 | Δ | Sakana Fugu-Ultra |
|---|---|---|---|
| Knowledge | Claude Opus 564.7 | Margin→ 30.8 | Sakana Fugu-Ultra95.5 |
| Coding | Claude Opus 589.5 | Margin← 25.0 | Sakana Fugu-Ultra64.5 |
| Multimodal | Claude Opus 566.9 | Margin→ 19.7 | Sakana Fugu-Ultra86.6 |
| Agentic | Claude Opus 590.8 | Margin← 8.7 | Sakana Fugu-Ultra82.1 |
| Reasoning | Claude Opus 590.4 | Margin→ 3.2 | Sakana Fugu-Ultra93.6 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Pro
CodingA 79.2%B 73.7%Winner: Claude Opus 5Δ 5.5SWE-bench Pro: Claude Opus 5 scored 79.2%; Sakana Fugu-Ultra scored 73.7%. Claude Opus 5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Opus 5 | Sakana Fugu-Ultra | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Opus 5$5 input / $25 output | Sakana Fugu-UltraNot available | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Opus 5Not available | Sakana Fugu-UltraNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Opus 5Not available | Sakana Fugu-UltraNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Opus 5Not available | Sakana Fugu-Ultra1M | A complete context comparison is not available. |
Benchmark Deep Dive
AgenticClaude Opus 5 wins25 benchmarks
| Benchmark | Claude Opus 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| FrontierBench v0.1Source | 43.3% | — | Not comparable |
| BrowseCompSource | 90.8% | — | Not comparable |
| HLE w/ toolsSource | 64.7% | — | Not comparable |
| DeepSearchQASource | 95.0% | — | Not comparable |
| DRACOSource | 88.6% | — | Not comparable |
| BrowseComp (10-agent, prerelease)Source | 93.6% | — | Not comparable |
| OSWorld 2.0Source | 70.6% | — | Not comparable |
| MCP AtlasSource | 85.8% | — | Not comparable |
| MCP-Atlas claim coverageSource | 89.1% | — | Not comparable |
| LAB all-pass (Anthropic harness)Source | 23.58% | — | Not comparable |
| LAB criterion-pass (Anthropic harness)Source | 93.74% | — | Not comparable |
| LAB all-pass (Harvey held-out)Source | 11.7% | — | Not comparable |
| LAB criterion-pass (Harvey held-out)Source | 94.1% | — | Not comparable |
| GDPval-AASource | 1861 | — | Not comparable |
| Toolathlon-VerifiedSource | 80.6% | — | Not comparable |
| Toolathlon Verified Pass@3Source | 87.0% | — | Not comparable |
| Toolathlon Verified Pass³Source | 73.1% | — | Not comparable |
| Toolathlon Verified avg. turnsSource | 23.5 turns | — | Not comparable |
| AutomationBenchSource | 26.0% | — | Not comparable |
| AA Agentic IndexSource | 55.3% | — | Not comparable |
| GDPval-AASource | 68.0% | — | Not comparable |
| AA Tau3 BankingSource | 30.3% | — | Not comparable |
| AA BriefcaseSource | 1720 | — | Not comparable |
| aaTerminalBench21Source | 89.1% | — | Not comparable |
| Terminal-Bench 2.0Source | — | 82.1% | Not comparable |
CodingClaude Opus 5 wins16 benchmarks
| Benchmark | Claude Opus 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 96% | — | Not comparable |
| SWE-bench ProSource | 79.2% | 73.7% | Claude Opus 5 leads |
| SWE MultilingualSource | 89.5% | — | Not comparable |
| SWE MultimodalSource | 59.4% | — | Not comparable |
| deepSweSource | 68.8% | — | Not comparable |
| FrontierCode 1.1 MainSource | 53.4% | — | Not comparable |
| FrontierCode 1.1 ExtendedSource | 63.6% | — | Not comparable |
| ProgramBench (episode 1)Source | 83.0% | — | Not comparable |
| ProgramBenchSource | 93.0% | — | Not comparable |
| cursorBench32Source | 70.0% | — | Not comparable |
| AA Coding IndexSource | 78.0% | — | Not comparable |
| AA-SciCodeSource | 55.7% | — | Not comparable |
| Terminal-Bench 2.0Source | — | 82.1% | Not comparable |
| LiveCodeBench v6Source | — | 93.2% | Not comparable |
| LiveCodeBench ProSource | — | 90.8% | Not comparable |
| SciCodeSource | — | 58.7% | Not comparable |
ReasoningSakana Fugu-Ultra wins6 benchmarks
KnowledgeSakana Fugu-Ultra wins23 benchmarks
| Benchmark | Claude Opus 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| HLESource | 64.7% | — | Not comparable |
| HLE w/o toolsSource | 56.3% | 50% | Claude Opus 5 leads |
| HealthBench (raw)Source | 67.1% | — | Not comparable |
| HealthBench (length-adjusted)Source | 57.8% | — | Not comparable |
| HealthBench ProfessionalSource | 59.8% | — | Not comparable |
| HealthBench Professional (raw)Source | 73.4% | — | Not comparable |
| BioMysteryBench (human-solvable)Source | 90.1% | — | Not comparable |
| BioMysteryBench (human-difficult)Source | 49.4% | — | Not comparable |
| SpatialBench VerifiedSource | 72.5% | — | Not comparable |
| SingleCellBenchSource | 60.6% | — | Not comparable |
| ProteinGym HardSource | 47.7% | — | Not comparable |
| Protein DesignSource | 42.5% | — | Not comparable |
| Organic chemistry V2Source | 61.6% | — | Not comparable |
| Protocols (troubleshooting)Source | 61.1% | — | Not comparable |
| Protocols (understanding)Source | 78.4% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 60.7% | — | Not comparable |
| AA-GPQA DiamondSource | 93.2% | — | Not comparable |
| AA-HLESource | 52.6% | — | Not comparable |
| AA-Omniscience IndexSource | 31.3% | — | Not comparable |
| AA-Omniscience AccuracySource | 54.2% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 50.1% | — | Not comparable |
| GPQASource | — | 95.5% | Not comparable |
| GPQA-DSource | — | 95.5% | Not comparable |
Math5 benchmarks
Multilingual3 benchmarks
MultimodalSakana Fugu-Ultra wins10 benchmarks
| Benchmark | Claude Opus 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| Chartography (no tools)Source | 29.6% | — | Not comparable |
| Chartography (tools)Source | 83.0% | — | Not comparable |
| BenchCAD Vision2Code (no tools)Source | 0.366 | — | Not comparable |
| BenchCAD Vision2Code (tools)Source | 0.821 | — | Not comparable |
| GDP.pdf (no tools)Source | 83.4% | — | Not comparable |
| GDP.pdf (tools)Source | 85.5% | — | Not comparable |
| OfficeQASource | 78.1% | — | Not comparable |
| OfficeQA ProSource | 66.9% | — | Not comparable |
| AA-MMMU-ProSource | 84.7% | — | Not comparable |
| CharXivSource | — | 86.6% | Not comparable |
Frequently Asked Questions (6)
Which is better, Claude Opus 5 or Sakana Fugu-Ultra?
Claude Opus 5 and Sakana Fugu-Ultra are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.
Which is better for knowledge tasks, Claude Opus 5 or Sakana Fugu-Ultra?
Sakana Fugu-Ultra has the edge for knowledge tasks in this comparison, averaging 95.5 versus 64.7. Inside this category, HLE w/o tools is the benchmark that creates the most daylight between them.
Which is better for coding, Claude Opus 5 or Sakana Fugu-Ultra?
Claude Opus 5 has the edge for coding in this comparison, averaging 89.5 versus 64.5. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.
Which is better for reasoning, Claude Opus 5 or Sakana Fugu-Ultra?
Sakana Fugu-Ultra has the edge for reasoning in this comparison, averaging 93.6 versus 90.4. Claude Opus 5 stays close enough that the answer can still flip depending on your workload.
Which is better for agentic tasks, Claude Opus 5 or Sakana Fugu-Ultra?
Claude Opus 5 has the edge for agentic tasks in this comparison, averaging 90.8 versus 82.1. Sakana Fugu-Ultra stays close enough that the answer can still flip depending on your workload.
Which is better for multimodal and grounded tasks, Claude Opus 5 or Sakana Fugu-Ultra?
Sakana Fugu-Ultra has the edge for multimodal and grounded tasks in this comparison, averaging 86.6 versus 66.9. Claude Opus 5 stays close enough that the answer can still flip depending on your workload.