Model comparison
Claude Mythos 5 vs Sakana Fugu-Ultra
Head-to-head evidence from 6 shared benchmark results across 4 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Mythos 5 #1 (Supported); Sakana Fugu-Ultra unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Mythos 5 and Sakana Fugu-Ultra share 6 comparable benchmark results. 4 of 8 categories are comparable. 9 results are unique to Claude Mythos 5; 5 to Sakana Fugu-Ultra.
Updated July 23, 2026- Shared results
- 6
- Claude Mythos 5 only
- 9
- Sakana Fugu-Ultra only
- 5
- Comparable categories
- 4 / 8
Treat this as a split decision. Claude Mythos 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 knowledge is the priority.
Confidence note. This is a partial-evidence comparison with 6 shared benchmark results across 4 evidence categories; 4 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Mythos 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 Mythos 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 Mythos 5 | Δ | Sakana Fugu-Ultra |
|---|---|---|---|
| Knowledge | Claude Mythos 568.5 | Margin→ 27.0 | Sakana Fugu-Ultra95.5 |
| Coding | Claude Mythos 589.7 | Margin← 25.2 | Sakana Fugu-Ultra64.5 |
| Multimodal | Claude Mythos 593.5 | Margin← 6.9 | Sakana Fugu-Ultra86.6 |
| Agentic | Claude Mythos 587.0 | Margin← 4.9 | Sakana Fugu-Ultra82.1 |
| Reasoning | Claude Mythos 5Not measured | MarginNo overlap | Sakana Fugu-Ultra93.6 |
| Math | Claude Mythos 597.6 | MarginNo overlap | Sakana Fugu-UltraNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
CharXiv
MultimodalA 93.5%B 86.6%Winner: Claude Mythos 5Δ 6.9CharXiv: Claude Mythos 5 scored 93.5%; Sakana Fugu-Ultra scored 86.6%. Claude Mythos 5 wins this benchmark. - Source ↗
SWE-bench Pro
CodingA 80.3%B 73.7%Winner: Claude Mythos 5Δ 6.6SWE-bench Pro: Claude Mythos 5 scored 80.3%; Sakana Fugu-Ultra scored 73.7%. Claude Mythos 5 wins this benchmark. - Source ↗
Terminal-Bench 2.0
AgenticA 88%B 82.1%Winner: Claude Mythos 5Δ 5.9Terminal-Bench 2.0: Claude Mythos 5 scored 88%; Sakana Fugu-Ultra scored 82.1%. Claude Mythos 5 wins this benchmark. - Source ↗
GPQA
KnowledgeA 94.1%B 95.5%Winner: Sakana Fugu-UltraΔ 1.4GPQA: Claude Mythos 5 scored 94.1%; Sakana Fugu-Ultra scored 95.5%. Sakana Fugu-Ultra wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Mythos 5 | Sakana Fugu-Ultra | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Mythos 5$10 input / $50 output | Sakana Fugu-UltraNot available | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Mythos 5Not available | Sakana Fugu-UltraNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Mythos 5Not available | Sakana Fugu-UltraNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Mythos 51M+ | Sakana Fugu-Ultra1M | Claude Mythos 5 lists the larger context window. |
Benchmark Deep Dive
AgenticClaude Mythos 5 wins4 benchmarks
CodingClaude Mythos 5 wins6 benchmarks
| Benchmark | Claude Mythos 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95.5% | — | Not comparable |
| SWE-bench ProSource | 80.3% | 73.7% | Claude Mythos 5 leads |
| Terminal-Bench 2.0Source | 88.0% | 82.1% | Claude Mythos 5 leads |
| LiveCodeBench v6Source | — | 93.2% | Not comparable |
| LiveCodeBench ProSource | — | 90.8% | Not comparable |
| SciCodeSource | — | 58.7% | Not comparable |
Reasoning1 benchmarks
| Benchmark | Claude Mythos 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| MRCRv2Source | — | 93.6% | Not comparable |
KnowledgeSakana Fugu-Ultra wins4 benchmarks
Math1 benchmarks
| Benchmark | Claude Mythos 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| USAMO 2026Source | 97.6% | — | Not comparable |
Multilingual1 benchmarks
| Benchmark | Claude Mythos 5 | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| SWE MultilingualSource | 92.2% | — | Not comparable |
Frequently Asked Questions (5)
Which is better, Claude Mythos 5 or Sakana Fugu-Ultra?
Claude Mythos 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 Mythos 5 or Sakana Fugu-Ultra?
Sakana Fugu-Ultra has the edge for knowledge tasks in this comparison, averaging 95.5 versus 68.5. Inside this category, HLE w/o tools is the benchmark that creates the most daylight between them.
Which is better for coding, Claude Mythos 5 or Sakana Fugu-Ultra?
Claude Mythos 5 has the edge for coding in this comparison, averaging 89.7 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 Mythos 5 or Sakana Fugu-Ultra?
Claude Mythos 5 has the edge for agentic tasks in this comparison, averaging 87 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 Mythos 5 or Sakana Fugu-Ultra?
Claude Mythos 5 has the edge for multimodal and grounded tasks in this comparison, averaging 93.5 versus 86.6. Inside this category, CharXiv is the benchmark that creates the most daylight between them.
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