Llama 3.1 8B Instruct vs MiMo-V2.5
Pricing, context window and real answers (September 2026)
Llama 3.1 8B Instruct (Meta) and MiMo-V2.5 (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 | |
|---|---|---|
| Provider | Meta | Xiaomi |
| Input (per 1M tokens) | ¥8.94 | ¥25.02 |
| Output (per 1M tokens) | ¥14.3 | ¥50.04 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥16 | ¥50 |
| Context window | 131,072 tokens | 1,050,000 tokens |
| Release date | 7/23/2024 | 4/22/2026 |
| Input modalities | text | text, audio, image, video |
| Throughput (p50) | — | — |
| Arena · overall | #329 · ELO 1,211 | #96 · ELO 1,434 |
| Arena · Japanese | #243 · ELO 1,087 | #141 · ELO 1,321 |
| Arena · coding | #323 · ELO 1,260 | #81 · ELO 1,491 |
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, 71% less than MiMo-V2.5.
- On the Overall arena board, MiMo-V2.5 ranks higher (#96; Llama 3.1 8B Instruct is #329).
- On the Japanese arena board, MiMo-V2.5 ranks higher (#141; Llama 3.1 8B Instruct is #243).
- On the Coding arena board, MiMo-V2.5 ranks higher (#81; Llama 3.1 8B Instruct is #323).
- For long documents, MiMo-V2.5: 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
# Counting the 'r's in 'strawberry'
Let me spell the word out letter by letter:
| Position | Letter | Is it 'r'? |
|----------|--------|------------|
| 1 | **s** | ❌ |
| 2 | **t** | ❌ |
| 3 | **r** | ✅ (1) |
| 4 | **a** | ❌ |
| 5 | **w** | ❌ |
| 6 | **b** | ❌ |
| 7 | **e** | ❌ |
| 8 | **r** | ✅ (2) |
| 9 | **r** | ✅ (3) |
| 10 | **y** | ❌ |
## Answer: **3** 'r's
The three r's are found at positions **3**, **8**, and **9** in the word.
14.9s313 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
This error occurs because your `users` prop is `undefined` when the component tries to call `.map()` on it. This usually happens when:
1. The parent component doesn't pass a `users` prop
2. The `users` data is still loading (asynchronous operation)
3. There's a typo in the prop name when passing from parent
## How to Fix It
### 1. Add Default Props or Prop Validation
Add a default value for the `users` prop:
```jsx
function UserList({ users = [] }) {
return (
<ul>
{users.map(user => <li key={user.id}>{user.name}</li>)}
</ul>
);
}
// Or with PropTypes
import PropTypes from 'prop-types';
function UserList({ users }) {
return (
<ul>
{users.map(user => <li key…
11.2s808 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
# Code Review: `get_data` Function
## Issues Identified
| Category | Issue | Severity |
|----------|-------|----------|
| Style | Imports inside function body | Medium |
| Reliability | Bare `except` catches `KeyboardInterrupt`/`SystemExit` | High |
| Reliability | Silent failures — no logging | Medium |
| Readability | `== True` comparison (redundant) | Low |
| Readability | No docstring or type hints | Medium |
| Performance | Could use list comprehension | Low |
| Robustness | No exponential backoff on retries | Medium |
| Robustness | `r.json()` can fail silently under bare except | High |
| Style | Uninformative variable names (`r`, `i`) | Low |
| Config | Magic numbers hardcoded (`ti…
33.6s1854 output tokens
Frequently asked questions
- Which is cheaper, Llama 3.1 8B Instruct or MiMo-V2.5?
- Per 1M output tokens, Llama 3.1 8B Instruct is ¥14.3 and MiMo-V2.5 is ¥50.04 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 compare?
- Llama 3.1 8B Instruct takes 131,072 tokens; MiMo-V2.5 takes 1,050,000.
- Which ranks higher, Llama 3.1 8B Instruct or MiMo-V2.5?
- MiMo-V2.5 ranks higher on the public arena (Llama 3.1 8B Instruct #243, MiMo-V2.5 #141). Ranks move as the leaderboard updates.
- Can I use Llama 3.1 8B Instruct and MiMo-V2.5 with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "llama-3.1-8b-instruct" or "mimo-v2.5" 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 from the browser chat and the API. No monthly fee.