Model comparison

GLM 5.3 FlashX vs Hy4

Pricing, context window and real answers (November 2026)

GLM 5.3 FlashX (Z.ai) and Hy4 (Tencent), 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 5.3 FlashXtencent logoHy4
ProviderZ.aiTencent
Input (per 1M tokens)$0.407$0.8799
Output (per 1M tokens)$1.38$2.64
Typical cost (1,000 in + 500 out tokens × 1,000 calls)$1.10$2.20
Context window1,048,576 tokens1,000,000 tokens
Release date9/18/202611/4/2026
Input modalitiestext, image, videotext
Throughput (p50)307 tokens/s (n=19)—
Arena · overallUnrankedUnranked
Arena · JapaneseUnrankedUnranked
Arena · codingUnrankedUnranked

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, GLM 5.3 FlashX: $1.38 per 1M output tokens, 48% less than Hy4.
  • For long documents, GLM 5.3 FlashX: a 1,048,576-token context window against 1,000,000 for Hy4.
  • 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 5.3 FlashX

# Counting 'r's in "strawberry" **Step 1: Write out each letter with its position** | Position | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |----------|---|---|---|---|---|---|---|---|---|----| | Letter | s | t | r | a | w | b | e | r | r | y | **Step 2: Check each letter one by one** - Position 1: **s** → not an 'r' - Position 2: **t** → not an 'r' - Position 3: **r** → ✅ 'r' found (count: 1) - Position 4: **a** → not an 'r' - Position 5: **w** → not an 'r' - Position 6: **b** → not an 'r' - Position 7: **e** → not an 'r' - Position 8: **r** → ✅ 'r' found (count: 2) - Position 9: **r** → ✅ 'r' found (count: 3) - Position 10: **y** → not an 'r' **Step 3: Tally the results** The 'r's a…
4.1s549 output tokens

Hy4

The word **“strawberry”** is spelled: **s t r a w b e r r y** Step by step: 1. Check each letter: s, t, **r**, a, w, b, e, **r**, **r**, y 2. Mark the **r**’s: one after **t**, and two near the end before **y**. 3. Count them: 1 + 1 + 1 = **3** So, there are **3** ‘r’s in **“strawberry”**.
4.2s343 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 5.3 FlashX

## What's Happening The error means `users` is `undefined` at the time `UserList` renders. You're calling `.map()` on `undefined`, which JavaScript doesn't allow. This almost always happens for one of these reasons: 1. **The parent isn't passing the prop** — `<UserList />` with no `users` prop 2. **Data hasn't loaded yet** — you're fetching asynchronously, so the first render happens before the data arrives 3. **Prop name mismatch** — e.g., passing `user` but reading `users` 4. **Parent state initialized to `undefined`** — e.g., `useState()` instead of `useState([])` ## Fixes ### Option 1: Default parameter (simplest) ```jsx function UserList({ users = [] }) { return ( <ul>…
6.8s934 output tokens

Hy4

The error is caused by this line: ```js {users.map(user => <li key={user.id}>{user.name}</li>)} ``` At render time, `users` is `undefined`. Since `.map()` only exists on arrays, JavaScript tries to read `map` from `undefined` and throws: ```txt Cannot read properties of undefined (reading 'map') ``` Even though this is in a Node.js app, this specific error is happening during React rendering, likely server-side rendering or a Node-based build/render process. Common causes: 1. The parent component is not passing `users`. 2. The prop name is misspelled. 3. `users` comes from async data and is `undefined` on the first render. 4. Your API returns something like `{ users: [...] }`, but you…
20.3s1951 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 5.3 FlashX

# Code Review The function works, but there are several issues worth addressing — including one subtle bug caused by the bare `except`. ## Correctness issues (most important) 1. **Bare `except:` is dangerous and masks a bug.** It catches *everything*, including `KeyboardInterrupt` and `SystemExit` (so Ctrl+C during a retry sleep is swallowed). Worse: because your data-processing loop sits inside the `try`, a `KeyError` from a malformed item is treated as a network failure — triggering a pointless re-download of the URL and silently discarding the real error. Catch only `requests.RequestException` (and `ValueError` for JSON decode failures). 2. **Silent failure.** Returning `[]` on error…
36.9s5836 output tokens

Hy4

Here are the main improvement areas, followed by a possible rewrite. ## Key issues ### Readability / style - Move imports to the top of the module. - Use descriptive names: `response` instead of `r`, `attempt` instead of `i`. - `if item["active"] == True:` should be `if item.get("active") is True:` or simply `if item.get("active"):`, depending on intent. - The filtering loop can be a list comprehension. - Add type hints and a docstring. ### Performance - Repeated imports are cached by Python, so not a major cost, but top-level imports are cleaner. - Avoid sleeping after the final failed attempt. - Use `requests.Session` for connection pooling if this function may be called repeatedly or i…
110.2s10761 output tokens

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Frequently asked questions

Which is cheaper, GLM 5.3 FlashX or Hy4?
Per 1M output tokens, GLM 5.3 FlashX is $1.38 and Hy4 is $2.64 on FastMetal (US dollars, before tax), so GLM 5.3 FlashX is cheaper.
How do the context windows of GLM 5.3 FlashX and Hy4 compare?
GLM 5.3 FlashX takes 1,048,576 tokens; Hy4 takes 1,000,000.
Can I use GLM 5.3 FlashX and Hy4 with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "glm-5.3-flashx" or "hy4" 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 5.3 FlashX and Hy4 from the browser chat and the API. No monthly fee.

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