gpt-oss-20b vs Qwen3.8 27B
Pricing, context window and real answers (September 2026)
gpt-oss-20b (OpenAI) 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
 gpt-oss-20b |  Qwen3.8 27B | |
|---|---|---|
| Provider | OpenAI | Qwen |
| Input (per 1M tokens) | ¥5.36 | ¥80.41 |
| Output (per 1M tokens) | ¥25.02 | ¥571.84 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥18 | ¥366 |
| Context window | 131,072 tokens | 1,000,000 tokens |
| Release date | 8/5/2025 | 8/14/2026 |
| Input modalities | text | text, image, video |
| Throughput (p50) | — | — |
| Arena · overall | #252 · ELO 1,317 | #90 · ELO 1,437 |
| Arena · Japanese | #179 · ELO 1,256 | #91 · ELO 1,383 |
| Arena · coding | #232 · ELO 1,369 | #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, gpt-oss-20b: ¥25.02 per 1M output tokens, 96% less than Qwen3.8 27B.
- On the Overall arena board, Qwen3.8 27B ranks higher (#90; gpt-oss-20b is #252).
- On the Japanese arena board, Qwen3.8 27B ranks higher (#91; gpt-oss-20b is #179).
- On the Coding arena board, Qwen3.8 27B ranks higher (#67; gpt-oss-20b is #232).
- For long documents, Qwen3.8 27B: a 1,000,000-token context window against 131,072 for gpt-oss-20b.
- 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.
gpt-oss-20b
**Count of ‘r’ in “strawberry”: 3**
---
### Step‑by‑step reasoning
1. **Write out the word in individual letters**
```
s t r a w b e r r y
```
2. **Identify each ‘r’**
- The first ‘r’: appears after the “t” → **r**
- The second ‘r’: appears in the part “berry” → **r**
- The third ‘r’: the next letter after that → **r**
3. **Verify there are no more letters left**
The remaining letters are “b”, “e”, “y”, none of which are “r”.
4. **Count the identified ‘r’s**
1 (first) + 1 (second) + 1 (third) = **3**
---
### Quick recap
- Word: **strawberry**
- Letters containing “r”: positions 3, 8, and 9.
- Total count: **3**.
11.6s371 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…
gpt-oss-20b
### Why does the error happen?
`users.map(...)` can only run when **`users` is an array**.
The stack trace shows that the crash happens on line 12 of `UserList.js`, which is the
exact spot where the code tries to call `.map`.
The value that is being passed to `UserList` (or the initial value that the parent
creates) is **`undefined`** (or it could be `null`/`{}`). When JavaScript tries to
read `users.map`, it throws:
```
TypeError: Cannot read properties of undefined (reading 'map')
```
Typical reasons for this are:
1. The parent component **didn’t pass the `users` prop** at all.
2. The parent passed it but the value was **`undefined` / `null`** because data
hasn’t been loaded ye…
11.4s1303 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):…
gpt-oss-20b
Below is a quick “code‑review” style list that touches the three axes you asked for – **readability**, **performance**, and **best practices**.
After the bullet‑list I’ll paste a refactored version that incorporates the most common fixes.
---
## 1. Readability
| Issue | Why it hurts | Quick fix |
|-------|--------------|-----------|
| **Imports inside the function** | Every call recompiles the import tables and makes the module’s top‑level slower. | Move `import requests` and `import time` to the module’s global header. |
| **Bare `except:`** | Catches *everything* (KeyboardInterrupt, SystemExit, MemoryError, etc.) and swallows useful tracebacks. | Catch only the expected network-relate…
24.6s2267 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
Frequently asked questions
- Which is cheaper, gpt-oss-20b or Qwen3.8 27B?
- Per 1M output tokens, gpt-oss-20b is ¥25.02 and Qwen3.8 27B is ¥571.84 on FastMetal (yen, before tax), so gpt-oss-20b is cheaper.
- How do the context windows of gpt-oss-20b and Qwen3.8 27B compare?
- gpt-oss-20b takes 131,072 tokens; Qwen3.8 27B takes 1,000,000.
- Which ranks higher, gpt-oss-20b or Qwen3.8 27B?
- Qwen3.8 27B ranks higher on the public arena (gpt-oss-20b #179, Qwen3.8 27B #91). Ranks move as the leaderboard updates.
- Can I use gpt-oss-20b and Qwen3.8 27B with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "gpt-oss-20b" 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 gpt-oss-20b and Qwen3.8 27B from the browser chat and the API. No monthly fee.