Model comparison

GPT-6 Luna vs MiMo-V2.6-Flash

Pricing, context window and real answers (November 2026)

GPT-6 Luna (OpenAI) and MiMo-V2.6-Flash (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 LunaMiMo-V2.6-Flash
ProviderOpenAIXiaomi
Input (per 1M tokens)$0.1055$0.1477
Output (per 1M tokens)$0.5275$0.2954
Typical cost (1,000 in + 500 out tokens × 1,000 calls)$0.3693$0.2954
Context window1,050,000 tokens1,048,576 tokens
Release date9/22/20269/21/2026
Input modalitiesfile, image, texttext, image, video, audio
Throughput (p50)82 tokens/s (n=25)83 tokens/s (n=28)
Arena · overall#97 · ELO 1,441#85 · ELO 1,448
Arena · Japanese#73 · ELO 1,421#133 · ELO 1,359
Arena · coding#66 · ELO 1,506#60 · ELO 1,510

Prices are FastMetal's rates, before tax.

Rankings: LMArena leaderboard dataset (lmarena-ai/leaderboard-dataset), CC BY 4.0, snapshot 2026-10-28; category names mapped and ratings rounded by FastMetal.

Which should you pick?

  • On price, MiMo-V2.6-Flash: $0.2954 per 1M output tokens, 44% less than GPT-6 Luna.
  • On the Overall arena board, MiMo-V2.6-Flash ranks higher (#85; GPT-6 Luna is #97).
  • On the Japanese arena board, GPT-6 Luna ranks higher (#73; MiMo-V2.6-Flash is #133).
  • On the Coding arena board, MiMo-V2.6-Flash ranks higher (#60; GPT-6 Luna is #66).
  • For long documents, GPT-6 Luna: a 1,050,000-token context window against 1,048,576 for MiMo-V2.6-Flash.
  • 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 Luna

In **“strawberry”**, the letter **r** appears at positions 3, 8, and 9. So there are **3** “r”s.
2.7s94 output tokens

MiMo-V2.6-Flash

## Counting the 'r's in 'strawberry' **Step 1: Write out each letter of the word individually:** `s - t - r - a - w - b - e - r - r - y` **Step 2: Go through each letter one by one and check if it's an 'r':** | Position | Letter | Is it 'r'? | Running Count | |----------|--------|------------|---------------| | 1 | s | ❌ | 0 | | 2 | t | ❌ | 0 | | 3 | **r** | ✅ | **1** | | 4 | a | ❌ | 1 | | 5 | w | ❌ | 1 | | 6 | b | ❌ | 1 | | 7 | e | ❌ | 1 | | 8 | **r** | ✅ | **2** | | 9 | **r** | ✅ | **3** | | 10 | y | ❌ | 3 | **Answer: There are 3 'r's in 'strawberry'.** 🍓 The first 'r' appears at position 3 (after "st"), and the remaining two are the double 'rr' near the end of the word.
6.5s379 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 Luna

`users` is `undefined` when `UserList` renders, so calling `users.map(...)` throws. This often happens because the parent didn’t pass the prop or because data hasn’t loaded yet. If an empty list is acceptable until the data arrives, provide a default: ```jsx function UserList({ users = [] }) { return ( <ul> {users.map(user => ( <li key={user.id}>{user.name}</li> ))} </ul> ); } ``` Also check that the parent passes `users`: ```jsx <UserList users={users} /> ``` If `users` is loaded asynchronously, initialize it as an array: ```jsx const [users, setUsers] = useState([]); ``` If `null` is also possible, normalize it before mapping, for example `(users ?? […
3.8s289 output tokens

MiMo-V2.6-Flash

## Cause of the Error The error occurs because the `users` prop is `undefined` when the component first renders. When you try to call `.map()` on `undefined`, it throws: ``` TypeError: Cannot read properties of undefined (reading 'map') ``` This typically happens when: 1. The **parent component** hasn't passed `users` yet (e.g., data is still loading from an API) 2. The prop name **doesn't match** between parent and child 3. The prop is **intentionally optional** but used unconditionally ## Fixes ### 1. Default parameter value (simplest fix) Set a default value for `users` so it's always an array: ```js function UserList({ users = [] }) { return ( <ul> {users.map(user =>…
7.6s547 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 Luna

Key improvements: - Move imports to module scope. - Catch `requests.RequestException` instead of using a bare `except`; the current handler can hide programming errors as well as network failures. - Call `raise_for_status()` so unsuccessful HTTP responses are handled explicitly. - Use a list comprehension instead of building the result manually. - Replace `item["active"] == True` with `item.get("active") is True` if the field is expected to be the Boolean `True`. - Add backoff between attempts. A fixed two-second delay can make retries slower than necessary. - Decide whether failures should raise an exception or return `[]`. Returning `[]` makes a failed request indistinguishable from a suc…
16.5s1713 output tokens

MiMo-V2.6-Flash

# Code Review: `get_data` ## Issues Identified | Category | Issue | |----------|-------| | **Readability** | Imports inside function, vague names (`i`, `r`), no docstring/type hints | | **Performance** | Manual loop instead of list comprehension, no `requests.Session` (no connection reuse) | | **Best Practices** | Bare `except`, `== True`, silent failures, no backoff, no error propagation | --- ## Improved Version ```python import time import logging import requests from typing import Optional logger = logging.getLogger(__name__) def get_data( url: str, retries: int = 3, timeout: float = 10, backoff_factor: float = 2.0, ) -> Optional[list[dict]]: """ Fetch dat…
18.9s1208 output tokens

Compare on more prompts →

Frequently asked questions

Which is cheaper, GPT-6 Luna or MiMo-V2.6-Flash?
Per 1M output tokens, GPT-6 Luna is $0.5275 and MiMo-V2.6-Flash is $0.2954 on FastMetal (US dollars, before tax), so MiMo-V2.6-Flash is cheaper.
How do the context windows of GPT-6 Luna and MiMo-V2.6-Flash compare?
GPT-6 Luna takes 1,050,000 tokens; MiMo-V2.6-Flash takes 1,048,576.
Which ranks higher, GPT-6 Luna or MiMo-V2.6-Flash?
GPT-6 Luna ranks higher on the public arena (GPT-6 Luna #73, MiMo-V2.6-Flash #133). Ranks move as the leaderboard updates.
Can I use GPT-6 Luna and MiMo-V2.6-Flash with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "gpt-6-luna" or "mimo-v2.6-flash" 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 Luna and MiMo-V2.6-Flash from the browser chat and the API. No monthly fee.

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