Model comparison

GLM 5.3 vs Inkling

Pricing, context window and real answers (August 2026)

GLM 5.3 (Z.ai) and Inkling (Thinkingmachines), 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 5.3Inkling
ProviderZ.aiThinkingmachines
Input (per 1M tokens)¥250.18¥178.7
Output (per 1M tokens)¥786.28¥723.74
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥643¥541
Context window1,048,576 tokens524,288 tokens
Release date8/18/20267/17/2026
Input modalitiestexttext, image, audio
Arena · overallUnranked#71 · ELO 1,443
Arena · JapaneseUnrankedUnranked
Arena · codingUnranked#64 · ELO 1,496

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

Which should you pick?

  • On price, Inkling: ¥723.74 per 1M output tokens, 8% less than GLM 5.3.
  • For long documents, GLM 5.3: a 1,048,576-token context window against 524,288 for Inkling.
  • 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

# Counting 'r's in "strawberry" **Step 1: Spell out the word letter by letter.** s - t - r - a - w - b - e - r - r - y **Step 2: Go through each letter and mark the 'r's.** | Position | Letter | Is it 'r'? | |----------|--------|------------| | 1 | s | No | | 2 | t | No | | 3 | **r** | ✅ Yes (1st) | | 4 | a | No | | 5 | w | No | | 6 | b | No | | 7 | e | No | | 8 | **r** | ✅ Yes (2nd) | | 9 | **r** | ✅ Yes (3rd) | | 10 | y | No | **Step 3: Tally the results.** - 1st 'r' in "st**r**awberry" - 2nd 'r' in "strawbe**r**ry" - 3rd 'r' in "strawber**r**y" ## Answer: There are **3** 'r's in "strawberry." (Note: two of them appear together in the "rr" near the end, which is easy to miss when c…
5.8s493 output tokens

Inkling

Let's break down the word **"strawberry"** letter by letter: 1. **s** 2. **t** 3. **r** ← (1st 'r') 4. **a** 5. **w** 6. **b** 7. **e** 8. **r** ← (2nd 'r') 9. **r** ← (3rd 'r') 10. **y** So the spelling is: s-t-**r**-a-w-b-e-**r**-**r**-y Counting them up: - One 'r' in "str" (the 3rd letter) - Two 'r's in "berry" (the 8th and 9th letters) **Total: 3 'r's** in "strawberry".**
2.4s417 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

## What's happening The error means `users` is `undefined` when the component renders. `undefined` doesn't have a `.map()` method, so JavaScript throws a `TypeError`. Since destructured props that aren't passed default to `undefined`, something upstream isn't providing the value you expect. ## Common causes 1. **The parent doesn't pass the prop, or uses a different name:** ```jsx <UserList /> {/* missing users */} <UserList userList={users} /> {/* prop name mismatch */} ``` 2. **Async data hasn't loaded yet** — the component renders before an API call completes, and the initial value is `undefined`: ```jsx const [users, setUsers] = useState(); // undefin…
17.1s1345 output tokens

Inkling

The error occurs because `users` is `undefined` when `UserList` renders, so `users.map` fails. This usually happens when: - The parent doesn't pass the prop (`<UserList />` instead of `<UserList users={...} />`) - Data is still loading (e.g., API hasn't returned yet) ## Quick Fix Provide a default empty array so `.map` always has an array to work with: ```jsx function UserList({ users = [] }) { return ( <ul> {users.map(user => <li key={user.id}>{user.name}</li>)} </ul> ); } ``` Alternatively, guard against undefined explicitly: ```jsx function UserList({ users }) { if (!users) return null; // or a loading state return ( <ul> {users.map(user => <li key={…
4.9s585 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

Here's a breakdown of the issues, followed by a refactored version. ## Readability - **Move imports to module level.** PEP 8 requires top-level imports; importing inside a function hides dependencies and adds overhead on every call (small, but pointless). - **`item["active"] == True`** → just `item.get("active")`. Comparing to `True` with `==` is flagged by PEP 8, and `.get()` avoids a `KeyError` if the key is missing. - **Use a list comprehension** instead of initializing a list and appending in a loop. - **Rename things.** `get_data` doesn't say what it does (`fetch_active_items`?), and `response` beats `r`. Use `_` for the unused loop counter. - **Magic numbers** (`2`, `10`) should be n…
75.0s6434 output tokens

Inkling

Here is a review with an improved version followed by explanations. ### Issues in the original - **Imports inside the function**: Re-importing on every call is inefficient. - **Bare `except:`**: Catches `SystemExit`, `KeyboardInterrupt`, etc. - **Silent failures**: No logging; errors disappear. - **Magic numbers**: `10`, `2`, `200` are hard-coded. - **Data validation missing**: Assumes `data` is a list and every item has `"active"`, `"name"`, and `"id"` (will crash with `KeyError`). - **Performance**: Uses `.append()` in a loop instead of a list comprehension. - **Ambiguous return**: `[]` means both "success with no results" and "total failure". ### Improved version ```python import loggi…
54.1s5649 output tokens

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Frequently asked questions

Which is cheaper, GLM 5.3 or Inkling?
Per 1M output tokens, GLM 5.3 is ¥786.28 and Inkling is ¥723.74 on FastMetal (yen, before tax), so Inkling is cheaper.
How do the context windows of GLM 5.3 and Inkling compare?
GLM 5.3 takes 1,048,576 tokens; Inkling takes 524,288.
Can I use GLM 5.3 and Inkling with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "glm-5.3" or "inkling" 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 and Inkling from the browser chat and the API. No monthly fee.

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