Kimi K3.1 Pro vs MiniMax M3
Pricing, context window and real answers (October 2026)
Kimi K3.1 Pro (Moonshot) and MiniMax M3 (MiniMax), 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
 Kimi K3.1 Pro |  MiniMax M3 | |
|---|---|---|
| Provider | Moonshot | MiniMax |
| Input (per 1M tokens) | $2.11 | $0.2954 |
| Output (per 1M tokens) | $10.55 | $1.17 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | $7.39 | $0.8757 |
| Context window | 1,048,576 tokens | 1,048,576 tokens |
| Release date | 10/23/2026 | 5/31/2026 |
| Input modalities | text, image, video | text, image, video |
| Throughput (p50) | — | 22 tokens/s (n=25) |
| Arena · overall | Unranked | #97 · ELO 1,440 |
| Arena · Japanese | Unranked | #96 · ELO 1,392 |
| Arena · coding | Unranked | #88 · ELO 1,496 |
Prices are FastMetal's rates, before tax.
Rankings: LMArena leaderboard dataset (lmarena-ai/leaderboard-dataset), CC BY 4.0, snapshot 2026-10-22; category names mapped and ratings rounded by FastMetal.
Which should you pick?
- On price, MiniMax M3: $1.17 per 1M output tokens, 89% less than Kimi K3.1 Pro.
- 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.
Kimi K3.1 Pro
There are **3** ‘r’s in **“strawberry.”**
1. Write out each letter: **s – t – r – a – w – b – e – r – r – y**
2. Locate the ‘r’s: positions **3, 8, and 9**.
3. Count them: **1 + 1 + 1 = 3**.
11.3s
MiniMax M3
# Counting 'r's in "strawberry"
Let me go through the word letter by letter:
**s** - t - **r** - a - w - b - e - **r** - **r** - y
| Position | Letter | Is it 'r'? |
|----------|--------|------------|
| 1 | s | No |
| 2 | t | No |
| 3 | **r** | ✓ (1st) |
| 4 | a | No |
| 5 | w | No |
| 6 | b | No |
| 7 | e | No |
| 8 | **r** | ✓ (2nd) |
| 9 | **r** | ✓ (3rd) |
| 10 | y | No |
## Answer: **3**
The word "strawberry" contains **three 'r's** — one at position 3, and two consecutive 'r's at positions 8 and 9.
25.6s455 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…
Kimi K3.1 Pro
## What's causing the error
The error means `users` is `undefined` when the component renders, and you can't call `.map()` on `undefined`. The component itself is fine — the problem is that whatever renders `<UserList />` either isn't passing the prop, or is passing a value that isn't an array yet.
The most common cause is **async data fetching**: the parent renders `UserList` before the data has loaded.
```jsx
function App() {
const [users, setUsers] = useState(); // ❌ undefined on first render
useEffect(() => {
fetch('/api/users')
.then(res => res.json())
.then(setUsers);
}, []);
return <UserList users={users} />; // users is undefined here initially
}
```
On…
36.3s
MiniMax M3
# Error Analysis
The error `Cannot read properties of undefined (reading 'map')` tells you that **`users` is `undefined`** when your component runs. JavaScript can't call `.map()` on `undefined`, so it throws this error.
The component itself is fine syntactically — the problem is that the `users` prop isn't being passed, or hasn't loaded yet.
## Common Causes
**1. The prop isn't passed at all:**
```jsx
<UserList /> // No users prop → users is undefined
```
**2. Data is still loading (async fetch):**
```jsx
const [users, setUsers] = useState(); // undefined initially
```
**3. API returns undefined:**
```jsx
const { data } = await fetch('/api/users').then(r => r.json());
setUsers(data);…
32.8s710 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):…
Kimi K3.1 Pro
The timeout and bounded retry loop are good starting points. The biggest issue is that failures—and even programming errors—are silently converted into retries and then `[]`.
### Suggested improvements
- **Avoid bare `except:`**. It catches `KeyboardInterrupt`, `KeyError`, JSON/schema errors, and other bugs. Retry only expected transient network failures; let malformed responses fail visibly.
- **Use a deliberate retry policy**. Retrying `401`, `403`, or `404` usually wastes time. Retry only transient statuses, use exponential backoff, and avoid sleeping after the final attempt.
- **Do not use `[]` for both failure and no results**. Prefer raising the final exception so callers can disting…
560.2s
MiniMax M3
## Code Review
This function works for the happy path, but it has several issues around error handling, retries, and readability. Here's a breakdown.
### 🐛 Bugs & Correctness Issues
| # | Issue | Why It Matters |
|---|-------|----------------|
| 1 | `except:` with no exception type | Swallows `KeyboardInterrupt`, `SystemExit`, and *everything else* (typos, `MemoryError`). You lose visibility into real failures. |
| 2 | Retries on every non‑200, including `4xx` | A `404` or `401` will never succeed by retrying — it just wastes time and rate-limit budget. |
| 3 | `if item["active"] == True` | Both linters (PEP 8 E712) and Python idiom prefer `if item["active"]:`. |
| 4 | `item["active"]` (…
33.4s3977 output tokens
Frequently asked questions
- Which is cheaper, Kimi K3.1 Pro or MiniMax M3?
- Per 1M output tokens, Kimi K3.1 Pro is $10.55 and MiniMax M3 is $1.17 on FastMetal (US dollars, before tax), so MiniMax M3 is cheaper.
- How do the context windows of Kimi K3.1 Pro and MiniMax M3 compare?
- Kimi K3.1 Pro takes 1,048,576 tokens; MiniMax M3 takes 1,048,576.
- Can I use Kimi K3.1 Pro and MiniMax M3 with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "kimi-k3.1-pro" or "minimax-m3" 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 Kimi K3.1 Pro and MiniMax M3 from the browser chat and the API. No monthly fee.