Llama 3.1 8B Instruct vs MiMo-V2.5-Pro
Pricing, context window and real answers (September 2026)
Llama 3.1 8B Instruct (Meta) and MiMo-V2.5-Pro (Xiaomi), 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
 Llama 3.1 8B Instruct | MiMo-V2.5-Pro | |
|---|---|---|
| Provider | Meta | Xiaomi |
| Input (per 1M tokens) | ¥8.94 | ¥77.73 |
| Output (per 1M tokens) | ¥14.3 | ¥155.47 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥16 | ¥155 |
| Context window | 131,072 tokens | 1,050,000 tokens |
| Release date | 7/23/2024 | 4/22/2026 |
| Input modalities | text | text |
| Throughput (p50) | — | — |
| Arena · overall | #329 · ELO 1,211 | #44 · ELO 1,467 |
| Arena · Japanese | #243 · ELO 1,087 | #52 · ELO 1,426 |
| Arena · coding | #323 · ELO 1,260 | #25 · ELO 1,521 |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, Llama 3.1 8B Instruct: ¥14.3 per 1M output tokens, 91% less than MiMo-V2.5-Pro.
- On the Overall arena board, MiMo-V2.5-Pro ranks higher (#44; Llama 3.1 8B Instruct is #329).
- On the Japanese arena board, MiMo-V2.5-Pro ranks higher (#52; Llama 3.1 8B Instruct is #243).
- On the Coding arena board, MiMo-V2.5-Pro ranks higher (#25; Llama 3.1 8B Instruct is #323).
- For long documents, MiMo-V2.5-Pro: a 1,050,000-token context window against 131,072 for Llama 3.1 8B Instruct.
- 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.
Llama 3.1 8B Instruct
To count the number of 'r's in 'strawberry', I will break down the word into its individual letters and examine each one. Here's the step-by-step process:
1. The word 'strawberry' consists of the following letters: s-t-r-a-w-b-e-r-r-y.
2. I will start by counting the letters that are not 'r'. The word has 1 's', 1 't', 1 'a', 1 'w', 1 'b', 1 'e', 1 'y'.
3. Next, I will count the number of 'r's. The word has 2 'r's, one of which is part of the letter combination 'rr'.
Therefore, there are 2 'r's in the word 'strawberry'.
9.7s169 output tokens
MiMo-V2.5-Pro
## Counting the r's in "strawberry"
Let me go through each letter one by one:
| Position | Letter | Is it 'r'? |
|----------|--------|------------|
| 1 | s | No |
| 2 | t | No |
| 3 | **r** | ✅ Yes (#1) |
| 4 | a | No |
| 5 | w | No |
| 6 | b | No |
| 7 | e | No |
| 8 | **r** | ✅ Yes (#2) |
| 9 | **r** | ✅ Yes (#3) |
| 10 | y | No |
**There are 3 r's in "strawberry."**
The word breaks down as **straw·ber·ry**, and the r's appear at the end of "staw" and then twice in the double-r of "rry."
8.3s313 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…
Llama 3.1 8B Instruct
The error `TypeError: Cannot read properties of undefined (reading 'map')` typically occurs when you're trying to access a property (in this case, `map`) on an object that is `undefined`.
In your case, the `users` prop passed to the `UserList` component is `undefined`. This is likely because the parent component that renders `UserList` is not passing the `users` prop, or the prop is not being properly initialized.
To fix this error, you can add a simple check to ensure that `users` is not `undefined` before trying to call `map` on it:
```javascript
function UserList({ users }) {
if (!users) return null; // or return a default message, e.g. "No users found"
return (
<ul>
{us…
7.9s292 output tokens
MiMo-V2.5-Pro
# Fixing `Cannot read properties of undefined (reading 'map')`
## The Problem
The error means `users` is `undefined` when the component first renders. This typically happens when:
1. **The parent component hasn't passed the `users` prop**
2. **The data is being fetched asynchronously and isn't available yet**
3. **The prop name is misspelled in the parent**
For example, the parent might be rendering it like this:
```jsx
// ❌ No users prop passed — `users` will be undefined
<UserList />
```
## Solutions
### 1. Add a Default Prop Value (Simple Fix)
```jsx
function UserList({ users = [] }) {
return (
<ul>
{users.map(user => <li key={user.id}>{user.name}</li>)}
</ul>
);
}…
14.4s680 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):…
Llama 3.1 8B Instruct
Here are some suggestions for improving the function's readability, performance, and best practices:
**Readability Improvements**
1. **Function name**: Consider renaming `get_data` to `fetch_active_items` to better reflect its purpose.
2. **Variable naming**: Use more descriptive variable names, such as `response` instead of `r`, and `active_items` instead of `result`.
3. **Code organization**: Break up the function into smaller, more focused sections. This will improve readability and make it easier to understand the logic.
4. **Type hints**: Add type hints for function parameters and return types to make the code more self-documenting.
**Performance Improvements**
1. **Use a more effic…
29.7s533 output tokens
MiMo-V2.5-Pro
# Code Review: `get_data` Function
## Issues Identified
```
┌──────────────────────────────────────────────────────────────┐
│ ISSUE SEVERITY MAP │
├──────────────────┬────────────┬──────────────────────────────┤
│ Issue │ Severity │ Category │
├──────────────────┼────────────┼──────────────────────────────┤
│ Bare except │ 🔴 High │ Error Handling / Best Prac. │
│ Silent failures │ 🔴 High │ Debuggability │
│ == True check │ 🟡 Medium │ Readability / PEP 8 │
│ Inline imports │ 🟡 Medium │ Best Practice │
│ No type hints │ 🟡 Medium │ Best Practice…
10.4s1572 output tokens
Frequently asked questions
- Which is cheaper, Llama 3.1 8B Instruct or MiMo-V2.5-Pro?
- Per 1M output tokens, Llama 3.1 8B Instruct is ¥14.3 and MiMo-V2.5-Pro is ¥155.47 on FastMetal (yen, before tax), so Llama 3.1 8B Instruct is cheaper.
- How do the context windows of Llama 3.1 8B Instruct and MiMo-V2.5-Pro compare?
- Llama 3.1 8B Instruct takes 131,072 tokens; MiMo-V2.5-Pro takes 1,050,000.
- Which ranks higher, Llama 3.1 8B Instruct or MiMo-V2.5-Pro?
- MiMo-V2.5-Pro ranks higher on the public arena (Llama 3.1 8B Instruct #243, MiMo-V2.5-Pro #52). Ranks move as the leaderboard updates.
- Can I use Llama 3.1 8B Instruct and MiMo-V2.5-Pro with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "llama-3.1-8b-instruct" or "mimo-v2.5-pro" 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 Llama 3.1 8B Instruct and MiMo-V2.5-Pro from the browser chat and the API. No monthly fee.