Model comparison

Fugu Ultra v2 vs Qwen3.8 27B

Pricing, context window and real answers (September 2026)

Fugu Ultra v2 (Sakana AI) and Qwen3.8 27B (Qwen), 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 Ultra v2qwen logoQwen3.8 27B
ProviderSakana AIQwen
Input (per 1M tokens)¥893.5¥80.41
Output (per 1M tokens)¥5,361¥571.84
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥3,574¥366
Context window1,000,000 tokens1,000,000 tokens
Release date9/11/20268/14/2026
Input modalitiestext, image, filetext, image, video
Throughput (p50)
Arena · overallUnranked#90 · ELO 1,437
Arena · JapaneseUnranked#91 · ELO 1,383
Arena · codingUnranked#67 · ELO 1,499

Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.

Which should you pick?

  • On price, Qwen3.8 27B: ¥571.84 per 1M output tokens, 89% less than Fugu Ultra v2.
  • 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 Ultra v2

**Answer: 3** **Step-by-step reasoning:** 1. **Write out the word letter by letter**, assigning each a position: | Position | Letter | Is it 'r'? | |---|---|---| | 1 | s | no | | 2 | t | no | | 3 | **r** | ✅ yes | | 4 | a | no | | 5 | w | no | | 6 | b | no | | 7 | e | no | | 8 | **r** | ✅ yes | | 9 | **r** | ✅ yes | | 10 | y | no | 2. **Tally the matches:** positions 3, 8, and 9 are 'r'. 3. **Sanity check by chunks:** "straw" contains one 'r' (str**a**w → the r in "str"), and "berry" contains two 'r's (be**rr**y). 1 + 2 = 3. 4. **Verify length:** the letters counted total 10, which matches the length of "strawberry" — so no letter was skipped or double-counted. **Conclusion:** There a…
10.2s435 output tokens

Qwen3.8 27B

The word is: **strawberry** Break it into letters: 1. s 2. t 3. r 4. a 5. w 6. b 7. e 8. r 9. r 10. y Now count the **r**’s: - 3rd letter: **r** - 8th letter: **r** - 9th letter: **r** So, there are **3** r’s in **strawberry**.
3.6s239 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 Ultra v2

## What the error means `TypeError: Cannot read properties of undefined (reading 'map')` means that when `UserList` rendered, `users` was `undefined`, and JavaScript can't read the `.map` property off `undefined`. The important detail: **the bug isn't really in `UserList`** — that's just where it surfaces. Destructuring `function UserList({ users })` does *not* throw when the prop is missing; it silently gives you `undefined`. The crash is deferred to the first property access, which is `.map` on line 12. So the real question is: why is `props.users` not an array? ## Why `users` is undefined **1. Async data hasn't arrived yet — by far the most common cause.** ```jsx const [users, setUs…
70.8s5286 output tokens

Qwen3.8 27B

The error means that `users` is `undefined` when `UserList` renders: ```jsx {users.map(...)} ``` JavaScript cannot call `.map()` on `undefined`. For example, this would cause the error: ```jsx <UserList /> ``` because `users` is not being passed in. ## Simple fix: give `users` a default value ```jsx function UserList({ users = [] }) { return ( <ul> {users.map(user => <li key={user.id}>{user.name}</li>)} </ul> ); } ``` Now if `users` is not passed in, it defaults to an empty array. ## Better fix: make sure the parent passes an array Wherever you use `UserList`, pass `users`: ```jsx <UserList users={users} /> ``` If `users` comes from an API or state, make sure it…
9.5s601 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 Ultra v2

# Final Code Review: `get_data` The function is compact and its intent is clear, but as written it will **fail silently in production**. Two defects dominate everything else: 1. The bare `except:` swallows every error — including `KeyboardInterrupt` and genuine logic bugs. 2. A total failure and a legitimately empty dataset both return `[]`, so callers cannot tell "the service is down" from "there are no active records." Together these mean an outage looks exactly like a successful empty response. Everything else below is meaningful improvement; those two are the difference between code that fails loudly and code that fails invisibly. --- ## 1. Correctness and error handling ### 1.1 `e…
281.1s23317 output tokens

Qwen3.8 27B

The function works at a basic level, but it has several readability, reliability, and best-practice issues. ## Main issues 1. **Imports inside the function** ```python import requests import time ``` Imports should normally be at the top of the module unless there is a specific reason to lazy-load them. 2. **Bare `except` is too broad** ```python except: time.sleep(2) ``` This catches almost everything, including `KeyboardInterrupt`, `SystemExit`, `KeyError`, `TypeError`, and other programming errors. It makes debugging harder and can retry failures that should not be retried. 3. **It retries on every non-`200` status** Retrying `401 Unauthorized`, `4…
205.9s13103 output tokens

Compare on more prompts →

Frequently asked questions

Which is cheaper, Fugu Ultra v2 or Qwen3.8 27B?
Per 1M output tokens, Fugu Ultra v2 is ¥5,361 and Qwen3.8 27B is ¥571.84 on FastMetal (yen, before tax), so Qwen3.8 27B is cheaper.
How do the context windows of Fugu Ultra v2 and Qwen3.8 27B compare?
Fugu Ultra v2 takes 1,000,000 tokens; Qwen3.8 27B takes 1,000,000.
Can I use Fugu Ultra v2 and Qwen3.8 27B with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "fugu-ultra-v2" or "qwen3.8-27b" 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 Ultra v2 and Qwen3.8 27B from the browser chat and the API. No monthly fee.

More comparisons with Fugu Ultra v2

More comparisons with Qwen3.8 27B