Fast-mode variant of [Opus 5](/anthropic/claude-opus-5) - identical capabilities with higher output speed at 2x pricing relative to regular Opus 5. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-…
Model details →Claude Opus 5 (Fast) vs Sakana: Fugu Ultra
Sakana: Fugu Ultra wins on 2 of 6 axes — pricing and capability skew in its favour for most workloads.
Fugu Ultra 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 route...
Model details →Side-by-side comparison
| Capability | Claude Opus 5 (Fast) | Sakana: Fugu Ultra | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 1M | 1M | Tie |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $10.00 | $5.00 | 🏆 Sakana: Fugu Ultra |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $50.00 | $30.00 | 🏆 Sakana: Fugu Ultra |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | Yes | Tie |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is Claude Opus 5 (Fast) better than Sakana: Fugu Ultra?
Sakana: Fugu Ultra wins on 2 of 6 axes — pricing and capability skew in its favour for most workloads.
What's the price difference between Claude Opus 5 (Fast) and Sakana: Fugu Ultra?
Input: $10.00 vs $5.00 per 1M tokens. Output: $50.00 vs $30.00 per 1M tokens.
What context windows do Claude Opus 5 (Fast) and Sakana: Fugu Ultra support?
Claude Opus 5 (Fast) supports up to 1M tokens. Sakana: Fugu Ultra supports up to 1M tokens.
Do both Claude Opus 5 (Fast) and Sakana: Fugu Ultra support tool calling?
Claude Opus 5 (Fast): yes. Sakana: Fugu Ultra: yes.
Compare Claude Opus 5 (Fast) with other models
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