Model comparison

Ember-1 vs GLM 5.2

Pricing, context window and real answers (September 2026)

Ember-1 (Fireworks) and GLM 5.2 (Z.ai), 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

Ember-1z-ai logoGLM 5.2
ProviderFireworksZ.ai
Input (per 1M tokens)¥536.1¥235.2
Output (per 1M tokens)¥2,680.5¥739.2
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥1,876¥605
Context window1,048,576 tokens1,048,576 tokens
Release date9/24/20266/16/2026
Input modalitiestext, imagetext
Throughput (p50)——
Arena · overallUnranked#38 · ELO 1,472
Arena · JapaneseUnranked#28 · ELO 1,452
Arena · codingUnranked#48 · ELO 1,510

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: ¥739.2 per 1M output tokens, 72% less than Ember-1.
  • 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.

Ember-1

# Counting the 'r's in "strawberry" **Step 1: Write out the word letter by letter** s - t - r - a - w - b - e - r - r - y **Step 2: Examine each letter one at a time** | 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 | **Step 3: Verify by splitting the word into parts** - "straw" → contains **1** r - "berry" → contains **2** r's - Total: 1 + 2 = **3** ## Answer The word "strawberry" contains **3** r's.
8.2s482 output tokens

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

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…

Ember-1

## The Cause The error means `users` is `undefined` when the component renders, so calling `.map()` on it fails. The component itself is fine — the problem is that the `users` prop isn't being provided (or isn't ready yet). The most common reasons this happens: 1. **Async data hasn't loaded yet** — the parent fetches users from an API, and the component renders before the fetch completes: ```jsx const [users, setUsers] = useState(); // undefined initially! ``` 2. **The prop isn't passed or is misspelled** in the parent: ```jsx <UserList user={users} /> // typo: should be "users" ``` 3. **Wrong data shape** — e.g., passing the whole response object instead of `response…
18.2s960 output tokens

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

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):…

Ember-1

# Code Review ## Bugs and correctness issues - **Bare `except:`** catches *everything* — including `KeyboardInterrupt` and, critically, `KeyError` from `item["active"]`. A malformed item in the response would be misinterpreted as a network failure, wasting all your retries on a data problem that retrying can't fix. - **Retrying all non-200 statuses** — a 404 or 401 will never succeed on retry. Only transient errors (connection failures, timeouts, 429, 5xx) are worth retrying. - **Wasted sleep on the final attempt** — the loop sleeps 2 seconds even after the last failure, before returning `[]`. - **Ambiguous return value** — `[]` means both "request failed" and "no active items." Callers ca…
95.0s5356 output tokens

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

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Frequently asked questions

Which is cheaper, Ember-1 or GLM 5.2?
Per 1M output tokens, Ember-1 is ¥2,680.5 and GLM 5.2 is ¥739.2 on FastMetal (yen, before tax), so GLM 5.2 is cheaper.
How do the context windows of Ember-1 and GLM 5.2 compare?
Ember-1 takes 1,048,576 tokens; GLM 5.2 takes 1,048,576.
Can I use Ember-1 and GLM 5.2 with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "ember-1" or "glm-5.2" 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 Ember-1 and GLM 5.2 from the browser chat and the API. No monthly fee.

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