Model comparison

Grok 4.7 vs Inkling

Pricing, context window and real answers (September 2026)

Grok 4.7 (xAI) and Inkling (Thinking Machines), 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

x-ai logoGrok 4.7Inkling
ProviderxAIThinking Machines
Input (per 1M tokens)¥276.2¥178.7
Output (per 1M tokens)¥828.6¥723.74
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥691¥541
Context window500,000 tokens524,288 tokens
Release date9/21/20267/17/2026
Input modalitiestext, image, filetext, image, audio
Throughput (p50)
Arena · overallUnranked#85 · ELO 1,440
Arena · JapaneseUnranked#63 · ELO 1,415
Arena · codingUnranked#78 · ELO 1,492

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, 13% less than Grok 4.7.
  • For long documents, Inkling: a 524,288-token context window against 500,000 for Grok 4.7.
  • 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.

Grok 4.7

The word "strawberry" consists of the letters S-T-R-A-W-B-E-R-R-Y. - The 3rd letter is R. - The 8th letter is R. - The 9th letter is R. This gives a total of 3 R's.
4.7s299 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…

Grok 4.7

The error happens because `users` is `undefined` when `UserList` renders, so calling `.map` on it fails. That usually means the parent rendered `<UserList />` (or `<UserList users={undefined} />`) before data was loaded, or the prop name doesn’t match. **Fix it in the component** so it tolerates a missing list: ```jsx function UserList({ users = [] }) { return ( <ul> {users.map(user => <li key={user.id}>{user.name}</li>)} </ul> ); } ``` Or guard the call: ```jsx function UserList({ users }) { return ( <ul> {(users ?? []).map(user => <li key={user.id}>{user.name}</li>)} </ul> ); } ``` **Also check the parent** so you pass an array once data exists: `…
12.8s393 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):…

Grok 4.7

## Review The function works for the happy path, but it hides failures, retries the wrong errors, and is harder to read and debug than it needs to be. ### Issues 1. **Imports inside the function** — move them to module level unless you have a strong reason (circular imports, optional dependency). 2. **Bare `except`** — swallows `KeyboardInterrupt`, `SystemExit`, and programming bugs. Catch specific exceptions. 3. **Retries non-retryable failures** — 4xx (except maybe 429) will not succeed on retry. Network errors and 5xx are the usual candidates. 4. **Sleeps after the last attempt** — wastes up to 2 seconds before returning `[]`. 5. **Unused loop variable** and vague names (`r`, `i`). 6.…
22.3s1525 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, Grok 4.7 or Inkling?
Per 1M output tokens, Grok 4.7 is ¥828.6 and Inkling is ¥723.74 on FastMetal (yen, before tax), so Inkling is cheaper.
How do the context windows of Grok 4.7 and Inkling compare?
Grok 4.7 takes 500,000 tokens; Inkling takes 524,288.
Can I use Grok 4.7 and Inkling with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "grok-4.7" 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 Grok 4.7 and Inkling from the browser chat and the API. No monthly fee.

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