Grok 4.6 vs MiMo-V2.5-Pro
Pricing, context window and real answers (October 2026)
Grok 4.6 (xAI) 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
 Grok 4.6 | MiMo-V2.5-Pro | |
|---|---|---|
| Provider | xAI | Xiaomi |
| Input (per 1M tokens) | $2.20 | $0.459 |
| Output (per 1M tokens) | $6.60 | $0.9179 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | $5.50 | $0.9179 |
| Context window | 500,000 tokens | 1,050,000 tokens |
| Release date | 8/12/2026 | 4/22/2026 |
| Input modalities | text, image, file | text |
| Throughput (p50) | 88 tokens/s (n=26) | 96 tokens/s (n=25) |
| Arena · overall | #72 · ELO 1,454 | #48 · ELO 1,468 |
| Arena · Japanese | #84 · ELO 1,402 | #67 · ELO 1,422 |
| Arena · coding | #59 · ELO 1,508 | #31 · ELO 1,522 |
Prices are FastMetal's rates, before tax.
Rankings: LMArena leaderboard dataset (lmarena-ai/leaderboard-dataset), CC BY 4.0, snapshot 2026-10-08; category names mapped and ratings rounded by FastMetal.
Which should you pick?
- On price, MiMo-V2.5-Pro: $0.9179 per 1M output tokens, 86% less than Grok 4.6.
- On the Overall arena board, MiMo-V2.5-Pro ranks higher (#48; Grok 4.6 is #72).
- On the Japanese arena board, MiMo-V2.5-Pro ranks higher (#67; Grok 4.6 is #84).
- On the Coding arena board, MiMo-V2.5-Pro ranks higher (#31; Grok 4.6 is #59).
- For long documents, MiMo-V2.5-Pro: a 1,050,000-token context window against 500,000 for Grok 4.6.
- 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.
Grok 4.6
The word "strawberry" consists of the following letters in order:
s-t-r-a-w-b-e-r-r-y
Checking each one:
- s: not r
- t: not r
- r: yes (count = 1)
- a: not r
- w: not r
- b: not r
- e: not r
- r: yes (count = 2)
- r: yes (count = 3)
- y: not r
There are exactly 3 r's.
Final answer: 3
3.9s451 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…
Grok 4.6
**The error happens because `users` is `undefined` when `.map()` is called.**
`UserList` destructures `{ users }` from its props. If the parent doesn't pass a `users` prop (or passes `undefined`/`null`), `users` is `undefined` and `undefined.map` throws.
This is extremely common when:
- Data is loaded asynchronously (initial render happens before the fetch finishes).
- The parent component forgets to pass the prop or uses a different name.
- The component is rendered before the data is ready (e.g. in a loading state).
### Quick fixes
**1. Default to an empty array (recommended)**
```jsx
function UserList({ users = [] }) {
return (
<ul>
{users.map(user => (
<li key={us…
20.3s598 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):…
Grok 4.6
Here is a focused review of the function, followed by a cleaned-up version.
## Issues
**Imports inside the function**
`requests` and `time` should live at module level. Importing on every call is slower, hides dependencies, and is harder to mock in tests.
**Bare `except:`**
This swallows `KeyboardInterrupt`, `SystemExit`, and programming errors. Catch `requests.RequestException` (network/timeout/HTTP adapter errors) and JSON/`KeyError`/`TypeError` separately.
**Retrying the wrong things**
A 404 or 400 will never succeed on retry. Retry transient failures (timeouts, connection errors, 429, 5xx). Fail fast on most 4xx responses.
**Sleep after the last attempt**
On the final failur…
27.9s1770 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, Grok 4.6 or MiMo-V2.5-Pro?
- Per 1M output tokens, Grok 4.6 is $6.60 and MiMo-V2.5-Pro is $0.9179 on FastMetal (US dollars, before tax), so MiMo-V2.5-Pro is cheaper.
- How do the context windows of Grok 4.6 and MiMo-V2.5-Pro compare?
- Grok 4.6 takes 500,000 tokens; MiMo-V2.5-Pro takes 1,050,000.
- Which ranks higher, Grok 4.6 or MiMo-V2.5-Pro?
- MiMo-V2.5-Pro ranks higher on the public arena (Grok 4.6 #84, MiMo-V2.5-Pro #67). Ranks move as the leaderboard updates.
- Can I use Grok 4.6 and MiMo-V2.5-Pro with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "grok-4.6" 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 Grok 4.6 and MiMo-V2.5-Pro from the browser chat and the API. No monthly fee.