GPT-5.6 Terra vs Qwen3.8 Max
Pricing, context window and real answers (August 2026)
GPT-5.6 Terra (OpenAI) and Qwen3.8 Max (Qwen), 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
 GPT-5.6 Terra |  Qwen3.8 Max | |
|---|---|---|
| Provider | OpenAI | Qwen |
| Input (per 1M tokens) | ¥357.4 | ¥357.4 |
| Output (per 1M tokens) | ¥2,144.4 | ¥1,072.2 |
| Typical cost (1,000 in + 500 out tokens × 1,000 calls) | ¥1,430 | ¥894 |
| Context window | 1,050,000 tokens | 1,000,000 tokens |
| Release date | 7/9/2026 | 8/3/2026 |
| Input modalities | file, image, text | text, image |
| Arena · overall | #34 · ELO 1,468 | Unranked |
| Arena · Japanese | Unranked | Unranked |
| Arena · coding | #22 · ELO 1,521 | Unranked |
Prices are FastMetal's yen rates before tax. Arena ranks are as of the latest leaderboard scrape.
Which should you pick?
- On price, Qwen3.8 Max: ¥1,072.2 per 1M output tokens, 50% less than GPT-5.6 Terra.
- For long documents, GPT-5.6 Terra: a 1,050,000-token context window against 1,000,000 for Qwen3.8 Max.
- 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-5.6 Terra
“strawberry” is spelled:
s t **r** a w b e **r** **r** y
There are **3** occurrences of the letter **r**.
3.6s71 output tokens
Qwen3.8 Max
The word **strawberry** is spelled:
**s t r a w b e r r y**
Now count the letter **r**:
1. s
2. t
3. **r** ← first r
4. a
5. w
6. b
7. e
8. **r** ← second r
9. **r** ← third r
10. y
There are **3** letters **r** in **strawberry**.
3.5s156 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-5.6 Terra
The error means `users` is `undefined` when `UserList` renders, so React tries to evaluate:
```js
users.map(...)
```
But `.map()` only exists on arrays.
Common causes:
- The parent component does not pass a `users` prop.
- The user data is loaded asynchronously and has not arrived on the first render.
- The API response shape differs from what you expect, e.g. data is in `response.data.users` rather than `response.data`.
- The parent initializes its user state as `undefined` or `null`.
## Fix options
### 1. Initialize users as an empty array
In the parent component:
```jsx
const [users, setUsers] = useState([]);
```
Then pass it normally:
```jsx
<UserList users={users} />
```
An e…
5.8s559 output tokens
Qwen3.8 Max
The error means `users` is `undefined` when `UserList` tries to render:
```js
{users.map(user => ...)}
```
JavaScript cannot call `.map()` on `undefined`, so React throws:
```text
Cannot read properties of undefined (reading 'map')
```
## Most likely cause
The parent component is rendering `UserList` without passing a valid `users` array, or it is passing `users` before the data has loaded.
For example:
```jsx
<UserList />
```
or:
```jsx
<UserList users={undefined} />
```
or:
```jsx
const [users, setUsers] = useState(); // undefined initially
```
Then later:
```jsx
<UserList users={users} />
```
On the first render, `users` is still `undefined`.
---
## Fix 1: Give `users` a d…
17.7s1020 output tokens
Professional Email
Write a professional email to a client explaining that the project delivery will be delayed by two weeks due to unexpected technical challenges discovered during integration testing. The tone should be apologetic but con…
GPT-5.6 Terra
Subject: Project Delivery Update and Revised Timeline
Dear [Client Name],
I’m writing to update you on the project timeline. During integration testing, our team identified several unexpected technical challenges that require additional resolution and validation to ensure the final delivery meets the agreed quality, performance, and reliability standards.
As a result, we need to extend the delivery date by two weeks. We sincerely apologize for the inconvenience this may cause and understand the importance of this project to your plans. While this adjustment is necessary, we are confident that the additional time will allow us to deliver a stable, fully tested solution.
**Revised Timeline…
6.0s351 output tokens
Qwen3.8 Max
Subject: Revised Project Delivery Timeline – Updated Schedule and Next Steps
Dear [Client Name],
I hope this message finds you well.
I am writing to provide an update on the current status of the project and to inform you that, during our recent integration testing phase, we encountered several unexpected technical challenges that will impact the original delivery timeline. After careful review with the technical team, we now anticipate the revised delivery date will be [insert date – two weeks from original delivery date].
Please accept my sincere apologies for this delay. We understand the importance of this project and the expectations tied to the original schedule. While this situati…
11.9s547 output tokens
Frequently asked questions
- Which is cheaper, GPT-5.6 Terra or Qwen3.8 Max?
- Per 1M output tokens, GPT-5.6 Terra is ¥2,144.4 and Qwen3.8 Max is ¥1,072.2 on FastMetal (yen, before tax), so Qwen3.8 Max is cheaper.
- How do the context windows of GPT-5.6 Terra and Qwen3.8 Max compare?
- GPT-5.6 Terra takes 1,050,000 tokens; Qwen3.8 Max takes 1,000,000.
- Can I use GPT-5.6 Terra and Qwen3.8 Max with the same API key?
- Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "gpt-5.6-terra" or "qwen3.8-max" 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-5.6 Terra and Qwen3.8 Max from the browser chat and the API. No monthly fee.