Choose Anthropic: Claude Opus 5.5 if…
No advantage on the data we track — pick it for provider preference or output quality on your own prompts.
Sakana: Fugu Max comes out ahead on the data we track: 1 advantage and none for Anthropic: Claude Opus 5.5.
| Spec | Anthropic: Claude Opus 5.5 | Sakana: Fugu Max |
|---|---|---|
| Provider | Anthropic | Sakana |
| Input price (per 1M tokens) | $4.00 | $2.00 |
| Output price (per 1M tokens) | $20.00 | $6.00 |
| Blended price (3:1 input/output) | $8.00 | $3.00 |
| Cheaper than … of all models we track | 7% | 20% |
| Context window | 1M tokens (~1,500 pages) | 1M tokens (~1,500 pages) |
| Larger context than … of all models | 68% | 68% |
| Max output per response | 128K tokens (~96,000 words) | 128K tokens (~96,000 words) |
| Input types | text, image, file | text, image, file |
| Output types | text | text |
| Free variant | No | No |
| Listed since | 2026-09-22 | 2026-09-11 |
Monthly cost at list price for five common workloads. Token counts per unit are stated so you can scale them to your own traffic. A workload that does not fit a model's context window is marked rather than priced.
| Workload (per month) | Anthropic: Claude Opus 5.5 | Sakana: Fugu Max | Difference |
|---|---|---|---|
| Customer-support chatbot 50,000 conversations — each a 6-turn conversation (1,500 in / 400 out tokens) | $700 | $270 | Sakana: Fugu Max saves $430 |
| RAG search over documents 20,000 questions — each a question answered from ~8 retrieved passages (6,000 in / 500 out tokens) | $680 | $300 | Sakana: Fugu Max saves $380 |
| Coding / tool-using agent 2,000 tasks — each a multi-step task with tool calls and file context (60,000 in / 6,000 out tokens) | $720 | $312 | Sakana: Fugu Max saves $408 |
| Batch summarisation 10,000 documents — each a 6,000-word report summarised to a page (8,000 in / 600 out tokens) | $440 | $196 | Sakana: Fugu Max saves $244 |
| Long-document analysis 500 documents — each a 150-page contract or codebase read in one pass (100,000 in / 2,000 out tokens) | $220 | $106 | Sakana: Fugu Max saves $114 |
| Capability | Anthropic: Claude Opus 5.5 | Sakana: Fugu Max | What it lets you do |
|---|---|---|---|
| Tool / function calling | ✓ Yes | ✓ Yes | call your APIs and run agent loops |
| Structured output (JSON schema) | ✓ Yes | ✓ Yes | return JSON that validates against your schema |
| Reasoning / thinking mode | ✓ Yes | ✓ Yes | spend extra tokens thinking before answering hard problems |
| Image input | ✓ Yes | ✓ Yes | read screenshots, charts and scanned pages |
| Audio input | — | — | take speech or audio directly |
| File / PDF input | ✓ Yes | ✓ Yes | accept documents without your own parsing step |
| Image output | — | — | generate images, not just text |
| Built-in web search | ✓ Yes | ✓ Yes | answer from live web results |
| Seed (reproducible sampling) | — | — | repeat a generation for tests and evals |
| Log-probabilities | — | — | read token confidence for classification and scoring |
From each model's published parameters and input/output types. “—” means not advertised, not proven absent.
No advantage on the data we track — pick it for provider preference or output quality on your own prompts.
Sakana: Fugu Max comes out ahead on the data we track: 1 advantage and none for Anthropic: Claude Opus 5.5.
Sakana: Fugu Max is cheaper: $3.00 vs $8.00 per 1M tokens at a typical 3:1 input/output mix, 63% less. For 50,000 support conversations a month that is $270 against $700.
Anthropic: Claude Opus 5.5 costs $4.00 per 1M input tokens and $20.00 per 1M output tokens; Sakana: Fugu Max costs $2.00 input and $6.00 output. Output tokens are billed separately, so long answers shift the gap.
Both take 1M tokens per request — roughly 1,500 pages of text.
Tool calling — Anthropic: Claude Opus 5.5: yes, Sakana: Fugu Max: yes. JSON-schema structured output — Anthropic: Claude Opus 5.5: yes, Sakana: Fugu Max: yes.
Yes, both accept image input.
No free variant is listed for either; both are pay-per-token.
Anthropic: Claude Opus 5.5 can write up to 128K tokens (about 96,000 words) per response; Sakana: Fugu Max up to 128K (about 96,000 words).
Anthropic: Claude Opus 5.5 was listed on 2026-09-22; Sakana: Fugu Max on 2026-09-11.
Claude Opus 5.5 is Anthropic's flagship model for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5. It is particularly strong at multi-step changes in large codebases, code...
Full Anthropic: Claude Opus 5.5 specs →Fugu Max is the cost-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...
Full Sakana: Fugu Max specs →