MiMo-V2.6-Flash vs Solar Pro 4
Pricing, context window and real answers (September 2026)
MiMo-V2.6-Flash (Xiaomi) and Solar Pro 4 (Upstage), 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
| MiMo-V2.6-Flash | Solar Pro 4 | |
|---|---|---|
| Provider | Xiaomi | Upstage |
| Input (per 1M tokens) | ¥25.02 | ¥16.08 |
| Output (per 1M tokens) | ¥50.04 | ¥64.33 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥50 | ¥48 |
| Context window | 1,048,576 tokens | 524,288 tokens |
| Release date | 9/21/2026 | 8/10/2026 |
| Input modalities | text, image, video, audio | text |
| Throughput (p50) | — | — |
| Arena · overall | Unranked | #177 · ELO 1,376 |
| Arena · Japanese | Unranked | Unranked |
| Arena · coding | Unranked | #144 · ELO 1,449 |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, MiMo-V2.6-Flash: ¥50.04 per 1M output tokens, 22% less than Solar Pro 4.
- For long documents, MiMo-V2.6-Flash: a 1,048,576-token context window against 524,288 for Solar Pro 4.
- 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.
MiMo-V2.6-Flash
## Counting the 'r's in 'strawberry'
**Step 1: Write out each letter of the word individually:**
`s - t - r - a - w - b - e - r - r - y`
**Step 2: Go through each letter one by one and check if it's an 'r':**
| Position | Letter | Is it 'r'? | Running Count |
|----------|--------|------------|---------------|
| 1 | s | ❌ | 0 |
| 2 | t | ❌ | 0 |
| 3 | **r** | ✅ | **1** |
| 4 | a | ❌ | 1 |
| 5 | w | ❌ | 1 |
| 6 | b | ❌ | 1 |
| 7 | e | ❌ | 1 |
| 8 | **r** | ✅ | **2** |
| 9 | **r** | ✅ | **3** |
| 10 | y | ❌ | 3 |
**Answer: There are 3 'r's in 'strawberry'.** 🍓
The first 'r' appears at position 3 (after "st"), and the remaining two are the double 'rr' near the end of the word.
6.5s379 output tokens
Solar Pro 4
The word "strawberry" contains **3** 'r's. Here's the step-by-step breakdown:
1. **Spell out the word explicitly** to isolate each letter:
`s - t - r - a - w - b - e - r - r - y`
2. **Scan through the letters in order** and count every instance of the lowercase letter `r`:
- `s` → 0
- `t` → 0
- `r` → **1**
- `a` → 0
- `w` → 0
- `b` → 0
- `e` → 0
- `r` → **2**
- `r` → **3**
- `y` → 0
3. **Total the count**: The three `r`s appear at positions 3, 8, and 9 in the 10-letter word.
**Final count: 3**
11.4s215 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…
MiMo-V2.6-Flash
## Cause of the Error
The error occurs because the `users` prop is `undefined` when the component first renders. When you try to call `.map()` on `undefined`, it throws:
```
TypeError: Cannot read properties of undefined (reading 'map')
```
This typically happens when:
1. The **parent component** hasn't passed `users` yet (e.g., data is still loading from an API)
2. The prop name **doesn't match** between parent and child
3. The prop is **intentionally optional** but used unconditionally
## Fixes
### 1. Default parameter value (simplest fix)
Set a default value for `users` so it's always an array:
```js
function UserList({ users = [] }) {
return (
<ul>
{users.map(user =>…
7.6s547 output tokens
Solar Pro 4
### What's Causing the Error
The error `TypeError: Cannot read properties of undefined (reading 'map')` means that the `users` prop being passed to your `UserList` component is `undefined`. Since you're calling `.map()` directly on it, JavaScript throws an error because `undefined` doesn't have a `map` method.
This typically happens when:
- The parent component hasn't passed the `users` prop
- The prop is still loading (e.g., from an API call)
- The prop is conditionally undefined
---
### How to Fix It
You have a few options to handle this safely:
#### ✅ Option 1: Add a Default Prop Value (Recommended)
Provide a fallback empty array so `.map()` always has something to work with:
```j…
24.7s539 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):…
MiMo-V2.6-Flash
# Code Review: `get_data`
## Issues Identified
| Category | Issue |
|----------|-------|
| **Readability** | Imports inside function, vague names (`i`, `r`), no docstring/type hints |
| **Performance** | Manual loop instead of list comprehension, no `requests.Session` (no connection reuse) |
| **Best Practices** | Bare `except`, `== True`, silent failures, no backoff, no error propagation |
---
## Improved Version
```python
import time
import logging
import requests
from typing import Optional
logger = logging.getLogger(__name__)
def get_data(
url: str,
retries: int = 3,
timeout: float = 10,
backoff_factor: float = 2.0,
) -> Optional[list[dict]]:
"""
Fetch dat…
18.9s1208 output tokens
Solar Pro 4
Here’s a breakdown of the issues in the original function, followed by a refactored version and a detailed explanation of the improvements.
### 🔍 Key Issues in the Original Code
| Area | Problem |
|------|---------|
| **Import organization** | `import` inside the function is evaluated on every call. Imports should live at the top of the module. |
| **Exception handling** | Bare `except:` catches `SystemExit`, `KeyboardInterrupt`, and other fatal errors. Always catch specific exceptions (`requests.RequestException`). |
| **Loose equality** | `== True` is redundant and can cause subtle bugs. Use `if item["active"]:` or `.get()`. |
| **HTTP status handling** | Calling `.json()` only on `200`…
17.5s1172 output tokens
Frequently asked questions
- Which is cheaper, MiMo-V2.6-Flash or Solar Pro 4?
- Per 1M output tokens, MiMo-V2.6-Flash is ¥50.04 and Solar Pro 4 is ¥64.33 on FastMetal (yen, before tax), so MiMo-V2.6-Flash is cheaper.
- How do the context windows of MiMo-V2.6-Flash and Solar Pro 4 compare?
- MiMo-V2.6-Flash takes 1,048,576 tokens; Solar Pro 4 takes 524,288.
- Can I use MiMo-V2.6-Flash and Solar Pro 4 with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "mimo-v2.6-flash" or "solar-pro4" 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 MiMo-V2.6-Flash and Solar Pro 4 from the browser chat and the API. No monthly fee.