Model comparison

GPT-6 Astra vs MiMo-V2.5-Pro

Pricing, context window and real answers (September 2026)

GPT-6 Astra (OpenAI) 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

openai logoGPT-6 AstraMiMo-V2.5-Pro
ProviderOpenAIXiaomi
Input (per 1M tokens)¥1,717.72¥77.73
Output (per 1M tokens)¥8,588.62¥155.47
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥6,012¥155
Context window1,050,000 tokens1,050,000 tokens
Release date9/4/20264/22/2026
Input modalitiesfile, image, texttext
Arena · overallUnranked#41 · ELO 1,468
Arena · JapaneseUnranked#56 · ELO 1,421
Arena · codingUnranked#26 · ELO 1,520

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, 98% less than GPT-6 Astra.
  • 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.

GPT-6 Astra

“strawberry” is spelled **s-t-r-a-w-b-e-r-r-y**. The letter **r** appears in positions **3, 8, and 9**, so there are **3 r’s**.
3.8s85 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…

GPT-6 Astra

The error means **`users` is `undefined` when React renders `UserList`**, so calling `users.map(...)` fails. This commonly happens when the parent doesn’t pass the prop or when data hasn’t finished loading. ### 1. Default `users` to an empty array If an absent prop should mean “no users,” use a default value: ```jsx function UserList({ users = [] }) { return ( <ul> {users.map(user => ( <li key={user.id}>{user.name}</li> ))} </ul> ); } ``` This handles a missing or `undefined` prop, but **not `null` or other non-array values**. ### 2. Check where the prop comes from Make sure the parent passes an array. For data loaded asynchronously, initialize state to…
6.7s380 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):…

GPT-6 Astra

The function is compact, but its biggest issue is that **all failures silently become `[]`**, making an unavailable API indistinguishable from a successful response with no active items. ### Suggested improvements - **Move imports to module scope** for clarity and conventional organization. - **Avoid bare `except:`.** It catches everything, including `KeyboardInterrupt`, and hides bugs such as missing dictionary keys. - **Retry only transient failures**, such as connection errors, timeouts, rate limiting, and selected server errors. Retrying a `401` or `404` usually won’t help. - **Don’t sleep after the final failed attempt.** Use exponential backoff rather than a fixed delay. - **Use desc…
19.2s965 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, GPT-6 Astra or MiMo-V2.5-Pro?
Per 1M output tokens, GPT-6 Astra is ¥8,588.62 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 GPT-6 Astra and MiMo-V2.5-Pro compare?
GPT-6 Astra takes 1,050,000 tokens; MiMo-V2.5-Pro takes 1,050,000.
Can I use GPT-6 Astra and MiMo-V2.5-Pro with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "gpt-6-astra" 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 GPT-6 Astra and MiMo-V2.5-Pro from the browser chat and the API. No monthly fee.

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