Overview
Fugu Ultra v2 is the higher-performance model in Sakana AI's Fugu family. Rather than a single monolithic model, Fugu is a learned multi-agent orchestration system: a language model trained to...
Our take
What genuinely differentiates Fugu Ultra v2 from alternatives like Claude or ChatGPT is its foundational approach: it operates as a learned multi-agent orchestration system rather than a single monolithic model. This architecture underpins its capacity for complex reasoning and its 1,000,000-token context window, which is larger than many comparable models. For instance, a researcher needing to synthesise information from hundreds of pages of academic papers could input the entire body of text, including images, and direct the model to extract and summarise key findings or identify trends. Unlike other AI assistants that might require external plugins for web access or structured data, Fugu Ultra v2 offers native web search and structured JSON outputs, facilitating more integrated workflows. Its built-in reasoning capabilities make it suitable for tackling more challenging problems, positioning it as a tool for those who require advanced analytical support. Ideal for developers and researchers who need extensive context handling, vision capabilities, and reliable structured outputs, it comes at an above-average API cost of $5 per 1M input tokens. This tool is best suited for users prioritising advanced capabilities and large context windows over cost efficiency.
How Sakana: Fugu Ultra v2 stacks up
Among the 383 chatbots & llms tools in our directory, it ranks #3 of 369 on quality (9.2/10), 15% above the 369-tool average of 8.0, and its $5/1M input-token rate is in the premium end — 194% pricier than the 359-model average of $1.70/1M.
Weighing quality against cost, Sakana: Fugu Ultra v2's cost-per-quality-point of $0.54 places it at #313 of 337 for value among chatbots & llms tools.
Sakana: Fugu Ultra v2 in depth
Sakana: Fugu Ultra v2, built by Sakana AI, sits in the chatbots & llms space and is a paid tool starting at $5.00/1M tokens. Our editors rate it 9.2 out of 10 based on capability, ecosystem and value. It handles a context window of 1,000,000 tokens.
On the feature side, Sakana: Fugu Ultra v2 brings 1,000,000-token context window, vision (image input), reasoning / chain-of-thought and tool / function calling. These are the capabilities that most shape day-to-day use and separate it from thinner alternatives.
Its biggest strength is large 1,000,000-token context window, bigger than most models listed here, while the main trade-off to weigh is that above-average api pricing ($5 per 1m input tokens). Keep both in mind when deciding whether it fits your workflow.
Sakana: Fugu Ultra v2 is most often chosen for research and writing. If that matches your goals, it's a strong candidate to shortlist.
Key features
- ✓1,000,000-token context window
- ✓Vision (image input)
- ✓Reasoning / chain-of-thought
- ✓Tool / function calling
- ✓Structured (JSON) outputs
- ✓Native web search
- ✓Knowledge cutoff 2026-08-28
Pricing
Pros
- +Large 1,000,000-token context window, bigger than most models listed here
- +Built-in reasoning (chain-of-thought) mode for harder problems
- +Accepts images as input (vision-capable)
- +Supports tool / function calling for agent-style workflows
Cons
- −Above-average API pricing ($5 per 1M input tokens)
Who should use Sakana: Fugu Ultra v2
- →Anyone looking for a chatbots & llms tool from Sakana AI.
- →Teams and individuals focused on research and writing.
- →People who value large 1,000,000-token context window, bigger than most models listed here.
- →Workflows that need a 1,000,000 tokens context window.
Who should look elsewhere
- →Anyone who needs a free tier — this tool is paid only.
- →Those for whom above-average api pricing ($5 per 1m input tokens) is a dealbreaker.
Best for
10 Best Sakana: Fugu Ultra v2 Alternatives in 2026
Sakana: Fugu Ultra v2 is a strong chatbots & llms tool, but it is not the only option. Whether you are after a lower price, different features or a better fit for your workflow, here are the 10 best alternatives to Sakana: Fugu Ultra v2, ranked and compared.
Anthropic
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OpenAI
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Google DeepMind
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Sakana AI
Fugu Max is the cost-performance model in Sakana AI's Fugu family. Rather than a single monolithic model, Fugu is a…
DeepSeek
DeepSeek V4.1 Flash is a sparse mixture-of-experts model from DeepSeek, and the first built on the company's Causal…
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Sakana: Fugu Ultra v2 vs top alternatives
A side-by-side look at how Sakana: Fugu Ultra v2 stacks up against its closest rivals.
| Feature | Sakana: Fugu Ultra v2Sakana AI | ClaudeAnthropic | ChatGPTOpenAI | GeminiGoogle DeepMind |
|---|---|---|---|---|
| Quality score | 9.2 / 10 | 9.6 / 10 | 9.5 / 10 | 9.2 / 10 |
| Starting price | $5.00/1M tokens | $20/mo | $20/mo | $20/mo |
| Free tier | No | Yes — Free tier available | Yes — Free tier available | Yes — Free tier available |
| API input price | $5 / 1M tokens | $5 / 1M tokens | $5 / 1M tokens | $0.375 / 1M tokens |
| API output price | $30 / 1M tokens | $25 / 1M tokens | $25 / 1M tokens | $1.875 / 1M tokens |
| Speed | — | Fast | Fast | Fast |
| Context window | 1,000,000 tokens | 200K tokens | 128K tokens | 1M-2M tokens |
| Categories | Chatbots & LLMs | Chatbots & LLMs, Coding, Writing | Chatbots & LLMs, Coding, Writing | Chatbots & LLMs, Coding, Writing |
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Frequently asked questions
Q. Is Sakana: Fugu Ultra v2 free?
No — Sakana: Fugu Ultra v2 is a paid tool, starting at $5.00/1M tokens.
Q. How much does Sakana: Fugu Ultra v2 cost?
Sakana: Fugu Ultra v2 starts at $5.00/1M tokens. API usage is around $5 per 1M input tokens and $30 per 1M output tokens.
Q. What is Sakana: Fugu Ultra v2 best for?
Sakana: Fugu Ultra v2 is best suited to research and writing, within the chatbots & llms category.
Q. What are the best Sakana: Fugu Ultra v2 alternatives?
Popular alternatives to Sakana: Fugu Ultra v2 include Claude, ChatGPT, Gemini and OpenAI GPT Astra Latest. Each trades off price, quality and ecosystem differently.
Q. Is there a free alternative to Sakana: Fugu Ultra v2?
Yes. Claude, ChatGPT, Gemini offer a free tier, making them good starting points if you want to avoid an upfront subscription.
Q. Why switch from Sakana: Fugu Ultra v2?
Common reasons include pricing, specific feature gaps (Above-average API pricing ($5 per 1M input tokens)), data-privacy requirements, or simply wanting a tool that fits your stack better.
How we rate AI tools
Our quality score weighs capability on real tasks, breadth of features and integrations, pricing and value, and how actively the tool is maintained. Scores are editorial guidance, not benchmarks — always trial a tool on your own workflow before committing. Pricing and features change frequently, so verify current details on the official site.
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