Muse Spark 1.2 vs Qwen3.8 2.4T A95B
Pricing, context window and real answers (August 2026)
Muse Spark 1.2 (Meta) and Qwen3.8 2.4T A95B (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
 Muse Spark 1.2 |  Qwen3.8 2.4T A95B | |
|---|---|---|
| Provider | Meta | Qwen |
| Input (per 1M tokens) | ¥219.9 | ¥351.83 |
| Output (per 1M tokens) | ¥747.65 | ¥1,055.5 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥594 | ¥880 |
| Context window | 1,048,576 tokens | 1,048,576 tokens |
| Release date | 8/5/2026 | 8/12/2026 |
| Input modalities | text, image, video, file, audio | text |
| Arena · overall | #4 · ELO 1,498 | Unranked |
| Arena · Japanese | Unranked | Unranked |
| Arena · coding | #7 · ELO 1,533 | Unranked |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, Muse Spark 1.2: ¥747.65 per 1M output tokens, 29% less than Qwen3.8 2.4T A95B.
- 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.
Muse Spark 1.2
There are **3** 'r's in "strawberry".
Here is my reasoning step by step:
1. Write out the word and its spelling: **s-t-r-a-w-b-e-r-r-y**
2. Go through each letter one by one and check if it is an 'r':
* 1. s - not an 'r' -> count = 0
* 2. t - not an 'r' -> count = 0
* 3. **r** - yes, it's an 'r' -> count = 1
* 4. a - not an 'r' -> count = 1
* 5. w - not an 'r' -> count = 1
* 6. b - not an 'r' -> count = 1
* 7. e - not an 'r' -> count = 1
* 8. **r** - yes, it's an 'r' -> count = 2
* 9. **r** - yes, it's an 'r' -> count = 3
* 10. y - not an 'r' -> count = 3
3. Final total = **3**.
13.3s1123 output tokens
Qwen3.8 2.4T A95B
To count the number of **“r”**s in **“strawberry”**, spell it out letter by letter:
**s t r a w b e r r y**
Now check each letter:
1. s — not r
2. t — not r
3. r — yes, count 1
4. a — not r
5. w — not r
6. b — not r
7. e — not r
8. r — yes, count 2
9. r — yes, count 3
10. y — not r
So there are **3** “r”s in **strawberry**.
1.3s203 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…
Muse Spark 1.2
This error means `users` is `undefined` when the component tries to render.
You are calling `.map()` on `users` at line 12, but `.map()` only exists on arrays. If `users` is `undefined` or `null`, JavaScript throws: `Cannot read properties of undefined (reading 'map')`.
This usually happens for 2 reasons:
1. You didn't pass the `users` prop to the component: `<UserList />`
2. Your data is async and `users` is `undefined` on the first render. For example: `const [users, setUsers] = useState()` without an initial value, and the data hasn't been fetched yet.
### Fix it
You need to guarantee `users` is always an array before you call `.map()`.
#### 1. Best Fix: Give it a default value
U…
7.6s1142 output tokens
Qwen3.8 2.4T A95B
The error happens because `users` is `undefined` when React tries to render this line:
```js
{users.map(user => <li key={user.id}>{user.name}</li>)}
```
JavaScript cannot call `.map()` on `undefined`.
In your component:
```js
function UserList({ users }) {
return (
<ul>
{users.map(user => <li key={user.id}>{user.name}</li>)}
</ul>
);
}
```
React expects `users` to be an array, but something is rendering `<UserList />` without providing a valid `users` prop.
---
## Common causes
### 1. The parent component is not passing `users`
For example:
```js
<UserList />
```
Instead of:
```js
<UserList users={users} />
```
---
### 2. The data has not loaded yet
If `users…
10.9s1318 output tokens
Professional Email
Write a professional email to a client explaining that the project delivery will be delayed by two weeks due to unexpected technical challenges discovered during integration testing. The tone should be apologetic but con…
Muse Spark 1.2
Subject: Update on [Project Name] Delivery Timeline - Revised Delivery Date
Here is a polished, ready-to-send template you can use:
---
**Subject:** Project Update: Revised Timeline for [Project Name]
Dear [Client Name],
I hope you are well. I am writing to provide you with an important update regarding the delivery of [Project Name].
During our scheduled integration testing this week, our team discovered unexpected technical challenges related to [briefly specify, e.g., data migration between the new platform and your legacy CRM system]. While individual components performed as expected in isolation, these integration issues require additional development and thorough re-testing to en…
16.4s1349 output tokens
Qwen3.8 2.4T A95B
Subject: Updated Project Timeline – Revised Delivery Date
Dear [Client Name],
I hope this message finds you well.
I’m writing to provide an important update regarding the delivery timeline for [Project Name]. During our recent integration testing phase, we identified several unexpected technical challenges that require additional resolution to ensure the final deliverable meets the quality and performance standards we committed to.
After carefully reviewing the scope of these items with our technical team, we have determined that the project delivery will need to be extended by two weeks. I sincerely apologize for any inconvenience this may cause. Please be assured that we are taking imm…
4.6s449 output tokens
Frequently asked questions
- Which is cheaper, Muse Spark 1.2 or Qwen3.8 2.4T A95B?
- Per 1M output tokens, Muse Spark 1.2 is ¥747.65 and Qwen3.8 2.4T A95B is ¥1,055.5 on FastMetal (yen, before tax), so Muse Spark 1.2 is cheaper.
- How do the context windows of Muse Spark 1.2 and Qwen3.8 2.4T A95B compare?
- Muse Spark 1.2 takes 1,048,576 tokens; Qwen3.8 2.4T A95B takes 1,048,576.
- Can I use Muse Spark 1.2 and Qwen3.8 2.4T A95B with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "muse-spark-1.2" or "qwen3.8-2.4t-a95b" 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 Muse Spark 1.2 and Qwen3.8 2.4T A95B from the browser chat and the API. No monthly fee.