Model comparison

GLM 5.2 vs GPT-6 Astra

Pricing, context window and real answers (September 2026)

GLM 5.2 (Z.ai) and GPT-6 Astra (OpenAI), 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

z-ai logoGLM 5.2openai logoGPT-6 Astra
ProviderZ.aiOpenAI
Input (per 1M tokens)¥250.18¥1,717.72
Output (per 1M tokens)¥786.28¥8,588.62
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥643¥6,012
Context window1,048,576 tokens1,050,000 tokens
Release date6/16/20269/4/2026
Input modalitiestextfile, image, text
Arena · overall#37 · ELO 1,472Unranked
Arena · Japanese#27 · ELO 1,453Unranked
Arena · coding#48 · ELO 1,509Unranked

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

Which should you pick?

  • On price, GLM 5.2: ¥786.28 per 1M output tokens, 91% less than GPT-6 Astra.
  • For long documents, GPT-6 Astra: a 1,050,000-token context window against 1,048,576 for GLM 5.2.
  • 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.

GLM 5.2

To count the number of 'r's in the word 'strawberry', let's look at the word letter by letter: 1. **s** - no 'r' 2. **t** - no 'r' 3. **r** - this is the 1st 'r' 4. **a** - no 'r' 5. **w** - no 'r' 6. **b** - no 'r' 7. **e** - no 'r' 8. **r** - this is the 2nd 'r' 9. **r** - this is the 3rd 'r' 10. **y** - no 'r' Total count: 3 There are **3** 'r's in the word 'strawberry'.
2.6s439 output tokens

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

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…

GLM 5.2

The error `TypeError: Cannot read properties of undefined (reading 'map')` happens because the `users` prop being passed to your `UserList` component is currently `undefined`. When JavaScript tries to call `.map()` on `undefined`, it throws this error. Here are the best ways to fix this: ### Fix 1: Provide a default value (Recommended) You can provide a default empty array `[]` when destructuring the props. This ensures that even if `users` is not passed down, the `.map()` function will still have an array to iterate over (resulting in an empty list rather than a crash). ```jsx function UserList({ users = [] }) { return ( <ul> {users.map(user => <li key={user.id}>{user.name}</…
8.3s1006 output tokens

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

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):…

GLM 5.2

Here is a review of your Python function, broken down by readability, performance, and best practices, followed by a refactored version of the code. ### 1. Best Practices * **Move imports to the top:** Importing modules inside a function is generally discouraged. While Python caches imports, putting `import requests` and `import time` at the top of your file is the standard convention and improves readability. * **Avoid bare `except:` blocks:** Using a bare `except:` catches everything, including `KeyboardInterrupt` and `SystemExit`. This makes it hard to interrupt your program if it gets stuck in a loop. You should catch specific exceptions, such as `requests.exceptions.RequestException` (…
10.9s2061 output tokens

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

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Frequently asked questions

Which is cheaper, GLM 5.2 or GPT-6 Astra?
Per 1M output tokens, GLM 5.2 is ¥786.28 and GPT-6 Astra is ¥8,588.62 on FastMetal (yen, before tax), so GLM 5.2 is cheaper.
How do the context windows of GLM 5.2 and GPT-6 Astra compare?
GLM 5.2 takes 1,048,576 tokens; GPT-6 Astra takes 1,050,000.
Can I use GLM 5.2 and GPT-6 Astra with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "glm-5.2" or "gpt-6-astra" 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 GLM 5.2 and GPT-6 Astra from the browser chat and the API. No monthly fee.

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