Fugu Max vs GPT-5.6 Terra
Pricing, context window and real answers (September 2026)
Fugu Max (Sakana AI) and GPT-5.6 Terra (OpenAI), compared as you can actually call them on FastMetal. Both are served from the same OpenAI-compatible endpoint and API key; switching is a change to the model string.
Specs and pricing
| Fugu Max |  GPT-5.6 Terra | |
|---|---|---|
| Provider | Sakana AI | OpenAI |
| Input (per 1M tokens) | ¥357.4 | ¥357.4 |
| Output (per 1M tokens) | ¥1,072.2 | ¥2,144.4 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥894 | ¥1,430 |
| Context window | 1,000,000 tokens | 1,050,000 tokens |
| Release date | 9/11/2026 | 7/9/2026 |
| Input modalities | text, image, file | file, image, text |
| Throughput (p50) | — | — |
| Arena · overall | Unranked | #45 · ELO 1,466 |
| Arena · Japanese | Unranked | #20 · ELO 1,467 |
| Arena · coding | Unranked | #35 · ELO 1,518 |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, Fugu Max: ¥1,072.2 per 1M output tokens, 50% less than GPT-5.6 Terra.
- For long documents, GPT-5.6 Terra: a 1,050,000-token context window against 1,000,000 for Fugu Max.
- If in doubt, try both on the same key. Switching is a change to the model string, and each is billed at its own rate.
Real answers to the same prompts
Exactly what the FastMetal gateway returned, side by side. Not benchmark scores: actual output.
Count the number of 'r's in 'strawberry'
Count the number of 'r's in 'strawberry'. Explain your reasoning step by step.
Fugu Max
The word **“strawberry”** has **3** letters **“r”**.
Step by step:
1. Write the word: **s t r a w b e r r y**
2. Check each letter:
- s — no
- t — no
- **r** — yes, 1st
- a — no
- w — no
- b — no
- e — no
- **r** — yes, 2nd
- **r** — yes, 3rd
- y — no
So, the total number of **‘r’s** in **“strawberry”** is **3**.
3.7s261 output tokens
GPT-5.6 Terra
“strawberry” is spelled:
s t **r** a w b e **r** **r** y
There are **3** occurrences of the letter **r**.
3.6s71 output tokens
Debug This Error
I'm getting the following error in my Node.js application: TypeError: Cannot read properties of undefined (reading 'map') at UserList (/app/components/UserList.js:12:25) at renderWithHooks (/app/node_modules/rea…
Fugu Max
The error means `users` is `undefined` when `UserList` renders, so `users.map(...)` throws:
```js
function UserList({ users }) {
// if `users` is not passed, this is undefined
return (
<ul>
{users.map(user => <li key={user.id}>{user.name}</li>)}
</ul>
);
}
```
Common causes:
1. Parent renders `<UserList />` without the `users` prop.
2. State is initialized as `undefined`:
```js
const [users, setUsers] = useState();
```
3. Async data hasn’t loaded yet, but the component already renders.
4. The API returned something unexpected, e.g. `undefined`, an object, or an error response.
## Fixes
### 1. Default the prop to an empty array
```jsx
function UserList({ use…
10.6s1293 output tokens
GPT-5.6 Terra
The error means `users` is `undefined` when `UserList` renders, so React tries to evaluate:
```js
users.map(...)
```
But `.map()` only exists on arrays.
Common causes:
- The parent component does not pass a `users` prop.
- The user data is loaded asynchronously and has not arrived on the first render.
- The API response shape differs from what you expect, e.g. data is in `response.data.users` rather than `response.data`.
- The parent initializes its user state as `undefined` or `null`.
## Fix options
### 1. Initialize users as an empty array
In the parent component:
```jsx
const [users, setUsers] = useState([]);
```
Then pass it normally:
```jsx
<UserList users={users} />
```
An e…
5.8s559 output tokens
Code Review
Please review the following Python function and suggest improvements for readability, performance, and best practices: def get_data(url, retries=3): import requests import time for i in range(retries):…
Fugu Max
Here’s a review with concrete improvements.
## Main issues
1. **Bare `except:`**
- Catches everything, including `KeyboardInterrupt`, `SystemExit`, and programming errors.
- Catch `requests.RequestException` instead, plus `ValueError` for JSON parsing if needed.
2. **Retries everything, including non-retryable errors**
- A `404` or `401` will be retried even though retrying will not help.
- Retry only transient failures: network errors, `429`, and `5xx`.
3. **Fixed 2-second sleep**
- No exponential backoff. Repeated retries can hammer the server.
- Use exponential backoff, optionally with jitter.
4. **Silent failure**
- Returning `[]` after all retries makes it hard…
24.7s3795 output tokens
GPT-5.6 Terra
Here are the main areas to improve:
### Issues in the original code
- **Imports inside the function**: Move `requests` and `time` imports to module scope.
- **Bare `except:`**: This catches everything, including `KeyboardInterrupt` and programming errors. Catch `requests.RequestException` (and possibly JSON decoding errors) instead.
- **Status code check**: Prefer `response.raise_for_status()` or `response.ok` over manually checking only for `200`. Successful responses can include other 2xx status codes.
- **`== True`**: Use `if item.get("active"):` instead.
- **Potential `KeyError`**: `item["name"]`, `item["id"]`, and `item["active"]` can fail if the API response is incomplete. Use `.get(…
10.6s939 output tokens
Frequently asked questions
- Which is cheaper, Fugu Max or GPT-5.6 Terra?
- Per 1M output tokens, Fugu Max is ¥1,072.2 and GPT-5.6 Terra is ¥2,144.4 on FastMetal (yen, before tax), so Fugu Max is cheaper.
- How do the context windows of Fugu Max and GPT-5.6 Terra compare?
- Fugu Max takes 1,000,000 tokens; GPT-5.6 Terra takes 1,050,000.
- Can I use Fugu Max and GPT-5.6 Terra with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "fugu-max" or "gpt-5.6-terra" as the model. Each is billed at its own rate from the same prepaid balance.
Try both on one API key
Create an account and add credit to call Fugu Max and GPT-5.6 Terra from the browser chat and the API. No monthly fee.