Model comparison
Claude Fable 5 vs Sakana Fugu-Ultra
Head-to-head evidence from 3 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Fable 5 #2 (Supported); Sakana Fugu-Ultra unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Fable 5 and Sakana Fugu-Ultra share 3 comparable benchmark results. 3 of 8 categories are comparable. 31 results are unique to Claude Fable 5; 8 to Sakana Fugu-Ultra.
Updated July 23, 2026- Shared results
- 3
- Claude Fable 5 only
- 31
- Sakana Fugu-Ultra only
- 8
- Comparable categories
- 3 / 8
Treat this as a split decision. Claude Fable 5 makes more sense if coding is the priority or you need the larger 1M+ context window; Sakana Fugu-Ultra is the better fit if multimodal & grounded is the priority.
Confidence note. This is a partial-evidence comparison with 3 shared benchmark results across 2 evidence categories; 3 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Fable 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.
Claude Fable 5 gives you the larger context window at 1M+, compared with 1M for Sakana Fugu-Ultra.
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 Fable 5 | Δ | Sakana Fugu-Ultra |
|---|---|---|---|
| Multimodal | Claude Fable 557.9 | Margin→ 28.7 | Sakana Fugu-Ultra86.6 |
| Coding | Claude Fable 589.2 | Margin← 24.7 | Sakana Fugu-Ultra64.5 |
| Agentic | Claude Fable 584.6 | Margin← 2.5 | Sakana Fugu-Ultra82.1 |
| Reasoning | Claude Fable 5Not measured | MarginNo overlap | Sakana Fugu-Ultra93.6 |
| Knowledge | Claude Fable 5Not measured | MarginNo overlap | Sakana Fugu-Ultra95.5 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Pro
CodingA 80%B 73.7%Winner: Claude Fable 5Δ 6.3SWE-bench Pro: Claude Fable 5 scored 80%; Sakana Fugu-Ultra scored 73.7%. Claude Fable 5 wins this benchmark. - Source ↗
Terminal-Bench 2.0
AgenticA 84.3%B 82.1%Winner: Claude Fable 5Δ 2.2Terminal-Bench 2.0: Claude Fable 5 scored 84.3%; Sakana Fugu-Ultra scored 82.1%. Claude Fable 5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Fable 5 | Sakana Fugu-Ultra | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Fable 5$10 input / $50 output | Sakana Fugu-UltraNot available | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Fable 5Not available | Sakana Fugu-UltraNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Fable 5Not available | Sakana Fugu-UltraNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Fable 51M+ | Sakana Fugu-Ultra1M | Claude Fable 5 lists the larger context window. |
Benchmark Deep Dive
AgenticClaude Fable 5 wins13 benchmarks
| Benchmark | Claude Fable 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 84.3% | 82.1% | Claude Fable 5 leads |
| OSWorld-VerifiedSource | 85% | — | Not comparable |
| GDPval-AASource | 1748 | — | Not comparable |
| AA Agentic IndexSource | 52.8% | — | Not comparable |
| τ²-bench resultsSource | 98.5% | — | Not comparable |
| GDPval-AASource | 62.4% | — | Not comparable |
| AA BriefcaseSource | 1574 | — | Not comparable |
| AA AutomationBenchSource | 48.6% | — | Not comparable |
| AA EnterpriseOps-GymSource | 51.1% | — | Not comparable |
| AA Harvey LABSource | 93.6% | — | Not comparable |
| AA Tau3 BankingSource | 26.8% | — | Not comparable |
| terminalBenchHardSource | 62.9% | — | Not comparable |
| aaTerminalBench21Source | 84.6% | — | Not comparable |
CodingClaude Fable 5 wins12 benchmarks
| Benchmark | Claude Fable 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95% | — | Not comparable |
| SWE-bench ProSource | 80% | 73.7% | Claude Fable 5 leads |
| FrontierCode 1.1 MainSource | 53.5% | — | Not comparable |
| Terminal-Bench 2.0Source | 84.3% | 82.1% | Claude Fable 5 leads |
| cursorBench31Source | 70.6% | — | Not comparable |
| cursorBench32Source | 70.5% | — | Not comparable |
| VulcanBench v3Source | 87.0% | — | Not comparable |
| AA Coding IndexSource | 76.5% | — | Not comparable |
| AA-SciCodeSource | 60.2% | — | Not comparable |
| LiveCodeBench v6Source | — | 93.2% | Not comparable |
| LiveCodeBench ProSource | — | 90.8% | Not comparable |
| SciCodeSource | — | 58.7% | Not comparable |
Reasoning3 benchmarks
Knowledge9 benchmarks
| Benchmark | Claude Fable 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| Artificial Analysis Intelligence IndexSource | 59.9% | — | Not comparable |
| AA-GPQA DiamondSource | 92.6% | — | Not comparable |
| AA-HLESource | 53.3% | — | Not comparable |
| AA-Omniscience IndexSource | 40.2% | — | Not comparable |
| AA-Omniscience AccuracySource | 61.4% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 54.9% | — | Not comparable |
| GPQASource | — | 95.5% | Not comparable |
| GPQA-DSource | — | 95.5% | Not comparable |
| HLE w/o toolsSource | — | 50% | Not comparable |
MultimodalSakana Fugu-Ultra wins4 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Fable 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| AA-IFBenchSource | 63.5% | — | Not comparable |
Frequently Asked Questions (4)
Which is better, Claude Fable 5 or Sakana Fugu-Ultra?
Claude Fable 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 coding, Claude Fable 5 or Sakana Fugu-Ultra?
Claude Fable 5 has the edge for coding in this comparison, averaging 89.2 versus 64.5. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.
Which is better for agentic tasks, Claude Fable 5 or Sakana Fugu-Ultra?
Claude Fable 5 has the edge for agentic tasks in this comparison, averaging 84.6 versus 82.1. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Which is better for multimodal and grounded tasks, Claude Fable 5 or Sakana Fugu-Ultra?
Sakana Fugu-Ultra has the edge for multimodal and grounded tasks in this comparison, averaging 86.6 versus 57.9. Claude Fable 5 stays close enough that the answer can still flip depending on your workload.
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