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Sakana

Sakana Fugu-Ultra

Sakana Fugu-Ultra is a reasoning model from Sakana in the Sakana Fugu family. 8 benchmarks count toward its index, in 5 categories.

  • Closed weights
  • Reasoning
  • Input: text
  • Released 2026-06
RankedEnough results for an index.
IndexAll categories, out of 100.66.3±7.7Median 51.0
CoverageIndex weight that has results.80%
SpeedOutput tokens per second.—Median 67/s
First tokenSeconds to the first output token.—Median 1.3 s
Input / 1MUS dollars per 1M input tokens.—Median $0.60
Output / 1MUS dollars per 1M output tokens.—Median $2.55
ContextMaximum tokens in one request.1MMedian 262K
EloLMArena rating and rank.—Median 1422

Capabilities

Index per category, out of 100.
Out of 100
AgenticMulti-step tasks with tools.1 counted69.2—
CodingCode writing and repair.3 counted68.326 / 209
ReasoningLogic problems and puzzles.1 counted68.4—
MultimodalTasks with images and text.1 counted62.8—
KnowledgeFacts and expert knowledge.2 counted69.721 / 268
MultilingualTasks in many languages.None counted——
InstructionTasks with strict prompt rules.None counted——
MathMath problems.None counted——

Results

8 counted
BenchmarkThe benchmark name.ResultThe score from the source.PlacePlace among results on this benchmark.
Graduate-Level Google-Proof Q&AKnowledge95.5%2 / 141
LiveCodeBench v6Coding93.2%1 / 59
GPQA Diamond · BenchLMKnowledge95.5%2 / 84
MRCRv2Reasoning93.6%1 / 14
Scientific Code BenchmarkCoding58.7%3 / 35
SWE-bench ProCoding73.7%8 / 83
Humanity's Last Exam without toolsKnowledge50.0%9 / 53
Terminal-Bench 2.1 · BenchLMAgentic82.1%28 / 86
CharXiv ReasoningMultimodal86.6%16 / 49
LiveCodeBench ProCoding90.8%—

Sources

BenchLMCC BY-NC 4.0

History

5 releases
Index67.4 → 66.3
23 Oct 202612 Nov 2026

Questions

How good is Sakana Fugu-Ultra?
Its index is 66.3 out of 100. That is place 37 of 283 ranked models.
What is Sakana Fugu-Ultra best at?
Knowledge: 69.7 out of 100, place 21 of 268.
What is the context window of Sakana Fugu-Ultra?
1M tokens.
Is Sakana Fugu-Ultra open source?
No. Its weights are not published.
When was Sakana Fugu-Ultra released?
June 2026.

Badge

Sakana Fugu-Ultra on Inference360: place 37 of 283, index 66.3
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