DeepSeek V4.1 Flash vs Qwen3.7 Max
Pricing, context window and real answers (September 2026)
DeepSeek V4.1 Flash (DeepSeek) and Qwen3.7 Max (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
 DeepSeek V4.1 Flash |  Qwen3.7 Max | |
|---|---|---|
| Provider | DeepSeek | Qwen |
| Input (per 1M tokens) | ¥50.69 | ¥263.58 |
| Output (per 1M tokens) | ¥202.74 | ¥790.75 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥152 | ¥659 |
| Context window | 1,048,576 tokens | 1,000,000 tokens |
| Release date | 9/10/2026 | 5/21/2026 |
| Input modalities | text, image | text |
| Arena · overall | Unranked | #32 · ELO 1,474 |
| Arena · Japanese | Unranked | Unranked |
| Arena · coding | Unranked | #19 · ELO 1,525 |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, DeepSeek V4.1 Flash: ¥202.74 per 1M output tokens, 74% less than Qwen3.7 Max.
- For long documents, DeepSeek V4.1 Flash: a 1,048,576-token context window against 1,000,000 for Qwen3.7 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.
DeepSeek V4.1 Flash
The word **“strawberry”** has **3** letter **“r”**s.
Step-by-step:
1. Spell it out: **s t r a w b e r r y**
2. Find each **r**:
- Position 3: **r** in “str”
- Position 8: first **r** in “berry”
- Position 9: second **r** in “berry”
3. Total: **3**
**Answer: 3**
7.5s226 output tokens
Qwen3.7 Max
To count the number of 'r's in the word "strawberry", let's break the word down letter by letter from left to right:
1. **s** - not an 'r'
2. **t** - not an 'r'
3. **r** - This is the **1st** 'r'
4. **a** - not an 'r'
5. **w** - not an 'r'
6. **b** - not an 'r'
7. **e** - not an 'r'
8. **r** - This is the **2nd** 'r'
9. **r** - This is the **3rd** 'r'
10. **y** - not an 'r'
By examining each character individually, we can see that the letter 'r' appears in the 3rd, 8th, and 9th positions.
Therefore, there are **3** 'r's in "strawberry".
15.1s842 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…
DeepSeek V4.1 Flash
The error means that `users` is `undefined` when `UserList` renders, so JavaScript cannot call `.map()` on it.
Your component expects a `users` prop:
```jsx
function UserList({ users }) {
return (
<ul>
{users.map(user => <li key={user.id}>{user.name}</li>)}
</ul>
);
}
```
But it is being rendered without `users`, or `users` has not loaded yet.
Common causes:
1. Parent renders it without the prop:
```jsx
<UserList />
```
instead of:
```jsx
<UserList users={users} />
```
2. The prop name is different:
```jsx
<UserList userList={users} />
```
3. The data is fetched asynchronously and is initially `undefined`:
```jsx
const [users, setUsers] = useState();
useEffect(…
16.0s945 output tokens
Qwen3.7 Max
This error occurs because the `users` prop being passed to your `UserList` component is **`undefined`** at the time React tries to render it. JavaScript cannot call the `.map()` method on `undefined`, which throws the error.
This usually happens for one of three reasons:
1. **Asynchronous Data Fetching:** The parent component is fetching `users` from an API. On the *initial render*, the data hasn't arrived yet, so the variable is `undefined`.
2. **Missing Prop:** The parent component forgot to pass the `users` prop (e.g., `<UserList />` instead of `<UserList users={myUsers} />`).
3. **Incorrect State Initialization:** The parent component initialized its state as `undefined` or `null` inste…
34.9s1851 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):…
DeepSeek V4.1 Flash
Here are the main improvements:
- Move imports to module level.
- Avoid bare `except`; catch specific exceptions.
- Use a `requests.Session` for connection reuse.
- Retry only transient network/HTTP failures, not all errors.
- Use exponential backoff and don’t sleep after the final attempt.
- Use a list comprehension for readability/performance.
- Add type hints, logging, constants, and basic JSON validation.
- Avoid `== True`; use `is True` or a truthy check depending on API contract.
Example refactor:
```python
from __future__ import annotations
import logging
import time
from typing import Any
import requests
logger = logging.getLogger(__name__)
TIMEOUT = (3.05, 10) # connect time…
31.5s5142 output tokens
Qwen3.7 Max
Here is a comprehensive review of your function, broken down by readability, performance, and best practices, followed by a refactored version.
### 1. Readability & Style (PEP 8)
* **Imports inside the function:** Imports should generally be placed at the top of the file, not inside the function. This makes dependencies clear and avoids slight overhead on every function call.
* **`item["active"] == True`:** In Python, explicitly comparing to `True` is discouraged (PEP 8). You should just use `if item.get("active"):`. Using `.get()` also prevents `KeyError` if the key is missing.
* **Manual List Building:** The `for` loop with `.append()` can be replaced with a much cleaner and faster **list…
58.3s3301 output tokens
Frequently asked questions
- Which is cheaper, DeepSeek V4.1 Flash or Qwen3.7 Max?
- Per 1M output tokens, DeepSeek V4.1 Flash is ¥202.74 and Qwen3.7 Max is ¥790.75 on FastMetal (yen, before tax), so DeepSeek V4.1 Flash is cheaper.
- How do the context windows of DeepSeek V4.1 Flash and Qwen3.7 Max compare?
- DeepSeek V4.1 Flash takes 1,048,576 tokens; Qwen3.7 Max takes 1,000,000.
- Can I use DeepSeek V4.1 Flash and Qwen3.7 Max with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "deepseek-v4.1-flash" or "qwen3.7-max" 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 DeepSeek V4.1 Flash and Qwen3.7 Max from the browser chat and the API. No monthly fee.