Model comparison
GPT-5.5 Pro vs Sakana Fugu-Ultra
Head-to-head evidence from 1 shared benchmark result across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-5.5 Pro #38 (Estimated); Sakana Fugu-Ultra unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.5 Pro and Sakana Fugu-Ultra share 1 comparable benchmark result. 2 of 8 categories are comparable. 6 results are unique to GPT-5.5 Pro; 10 to Sakana Fugu-Ultra.
Updated July 23, 2026- Shared results
- 1
- GPT-5.5 Pro only
- 6
- Sakana Fugu-Ultra only
- 10
- Comparable categories
- 2 / 8
Treat this as a split decision. GPT-5.5 Pro makes more sense if agentic is the priority; Sakana Fugu-Ultra is the better fit if knowledge is the priority.
Confidence note. This is a partial-evidence comparison with 1 shared benchmark result across 1 evidence category; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
GPT-5.5 Pro 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 | GPT-5.5 Pro | Δ | Sakana Fugu-Ultra |
|---|---|---|---|
| Knowledge | GPT-5.5 Pro57.2 | Margin→ 38.3 | Sakana Fugu-Ultra95.5 |
| Agentic | GPT-5.5 Pro90.1 | Margin← 8.0 | Sakana Fugu-Ultra82.1 |
| Coding | GPT-5.5 ProNot measured | MarginNo overlap | Sakana Fugu-Ultra64.5 |
| Reasoning | GPT-5.5 ProNot measured | MarginNo overlap | Sakana Fugu-Ultra93.6 |
| Math | GPT-5.5 Pro48.1 | MarginNo overlap | Sakana Fugu-UltraNot measured |
| Multimodal | GPT-5.5 ProNot measured | MarginNo overlap | Sakana Fugu-Ultra86.6 |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.5 Pro | Sakana Fugu-Ultra | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.5 Pro$30 input / $180 output | Sakana Fugu-UltraNot available | A complete price comparison is not available. |
| Generation speedtokens per second | GPT-5.5 ProNot available | Sakana Fugu-UltraNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.5 ProNot available | Sakana Fugu-UltraNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.5 Pro1M | Sakana Fugu-Ultra1M | Listed context windows are equal. |
Benchmark Deep Dive
AgenticGPT-5.5 Pro wins2 benchmarks
Coding5 benchmarks
Reasoning2 benchmarks
KnowledgeSakana Fugu-Ultra wins4 benchmarks
Math3 benchmarks
Multimodal1 benchmarks
| Benchmark | GPT-5.5 Pro | Sakana Fugu-Ultra | Result |
|---|---|---|---|
| CharXivSource | — | 86.6% | Not comparable |
Frequently Asked Questions (3)
Which is better, GPT-5.5 Pro or Sakana Fugu-Ultra?
GPT-5.5 Pro 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, GPT-5.5 Pro or Sakana Fugu-Ultra?
Sakana Fugu-Ultra has the edge for knowledge tasks in this comparison, averaging 95.5 versus 57.2. Inside this category, HLE w/o tools is the benchmark that creates the most daylight between them.
Which is better for agentic tasks, GPT-5.5 Pro or Sakana Fugu-Ultra?
GPT-5.5 Pro has the edge for agentic tasks in this comparison, averaging 90.1 versus 82.1. Sakana Fugu-Ultra stays close enough that the answer can still flip depending on your workload.
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