Model comparison

Grok 4.6 vs MiMo-V2.5-Pro

Pricing, context window and real answers (August 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

x-ai logoGrok 4.6MiMo-V2.5-Pro
ProviderxAIXiaomi
Input (per 1M tokens)¥357.4¥77.73
Output (per 1M tokens)¥1,072.2¥155.47
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥894¥155
Context window500,000 tokens1,050,000 tokens
Release date8/12/20264/22/2026
Input modalitiestext, image, filetext
Arena · overallUnranked#38 · ELO 1,465
Arena · JapaneseUnranked#44 · ELO 1,422
Arena · codingUnranked#26 · ELO 1,519

Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.

Which should you pick?

  • On price, MiMo-V2.5-Pro: ¥155.47 per 1M output tokens, 85% less than Grok 4.6.
  • 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

Compare on more prompts →

Frequently asked questions

Which is cheaper, Grok 4.6 or MiMo-V2.5-Pro?
Per 1M output tokens, Grok 4.6 is ¥1,072.2 and MiMo-V2.5-Pro is ¥155.47 on FastMetal (yen, 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.
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.

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