Model comparison

Ember-1 vs gpt-oss-20b

Pricing, context window and real answers (September 2026)

Ember-1 (Fireworks) and gpt-oss-20b (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

Ember-1openai logogpt-oss-20b
ProviderFireworksOpenAI
Input (per 1M tokens)¥536.1¥5.36
Output (per 1M tokens)¥2,680.5¥25.02
Typical cost (1,000 in + 500 out tokens × 1,000 calls)¥1,876¥18
Context window1,048,576 tokens131,072 tokens
Release date9/24/20268/5/2025
Input modalitiestext, imagetext
Throughput (p50)——
Arena · overallUnranked#252 · ELO 1,317
Arena · JapaneseUnranked#179 · ELO 1,256
Arena · codingUnranked#232 · ELO 1,369

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

Which should you pick?

  • On price, gpt-oss-20b: ¥25.02 per 1M output tokens, 99% less than Ember-1.
  • For long documents, Ember-1: a 1,048,576-token context window against 131,072 for gpt-oss-20b.
  • 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

gpt-oss-20b

**Count of ‘r’ in “strawberry”: 3** --- ### Step‑by‑step reasoning 1. **Write out the word in individual letters** ``` s t r a w b e r r y ``` 2. **Identify each ‘r’** - The first ‘r’: appears after the “t” → **r** - The second ‘r’: appears in the part “berry” → **r** - The third ‘r’: the next letter after that → **r** 3. **Verify there are no more letters left** The remaining letters are “b”, “e”, “y”, none of which are “r”. 4. **Count the identified ‘r’s** 1 (first) + 1 (second) + 1 (third) = **3** --- ### Quick recap - Word: **strawberry** - Letters containing “r”: positions 3, 8, and 9. - Total count: **3**.
11.6s371 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

gpt-oss-20b

### Why does the error happen? `users.map(...)` can only run when **`users` is an array**. The stack trace shows that the crash happens on line 12 of `UserList.js`, which is the exact spot where the code tries to call `.map`. The value that is being passed to `UserList` (or the initial value that the parent creates) is **`undefined`** (or it could be `null`/`{}`). When JavaScript tries to read `users.map`, it throws: ``` TypeError: Cannot read properties of undefined (reading 'map') ``` Typical reasons for this are: 1. The parent component **didn’t pass the `users` prop** at all. 2. The parent passed it but the value was **`undefined` / `null`** because data hasn’t been loaded ye…
11.4s1303 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

gpt-oss-20b

Below is a quick “code‑review” style list that touches the three axes you asked for – **readability**, **performance**, and **best practices**. After the bullet‑list I’ll paste a refactored version that incorporates the most common fixes. --- ## 1. Readability | Issue | Why it hurts | Quick fix | |-------|--------------|-----------| | **Imports inside the function** | Every call recompiles the import tables and makes the module’s top‑level slower. | Move `import requests` and `import time` to the module’s global header. | | **Bare `except:`** | Catches *everything* (KeyboardInterrupt, SystemExit, MemoryError, etc.) and swallows useful tracebacks. | Catch only the expected network-relate…
24.6s2267 output tokens

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Frequently asked questions

Which is cheaper, Ember-1 or gpt-oss-20b?
Per 1M output tokens, Ember-1 is ¥2,680.5 and gpt-oss-20b is ¥25.02 on FastMetal (yen, before tax), so gpt-oss-20b is cheaper.
How do the context windows of Ember-1 and gpt-oss-20b compare?
Ember-1 takes 1,048,576 tokens; gpt-oss-20b takes 131,072.
Can I use Ember-1 and gpt-oss-20b with the same API key?
Yes. On FastMetal's OpenAI-compatible endpoint, switch by passing "ember-1" or "gpt-oss-20b" 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 gpt-oss-20b from the browser chat and the API. No monthly fee.

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