Short answer
Gemini 4 Carbon is not released. It is an internal Gemini 4 checkpoint that Google employees have been testing, first reported by Business Insider on October 9, 2026. One employee said its coding feels comparable to Anthropic's Claude Opus 5.5. There is no public benchmark, price or release date, and Google declined to comment. What you can use today is Gemini 4 Argon, the first Gemini 4 model, available on TeamoRouter as gemini-4-argon, and Claude Opus 5.5, the model Carbon is being compared to. When Carbon ships, it will appear on the pricing page under Google's own model ID, and switching is a one-line change.
What the leak says
Everything below comes from one report, Business Insider on October 9, 2026, and the outlets that repeated it:
- Google employees are testing a Gemini 4 checkpoint called Carbon on Jetski, Google's internal coding platform.
- One developer said Carbon's coding performance "feels comparable" to Claude Opus 5.5. That is a single impression, not a benchmark.
- Google declined to comment on internal testing and release plans.
What is not known
- Release date. None has been announced.
- Price. Not published.
- Name at launch. Reports disagree on whether Carbon is a newer checkpoint that will ship under the Argon name or a separate model.
- Benchmarks. None are public.
Carbon, Argon and Opus 5.5
| Gemini 4 Carbon | Gemini 4 Argon | Claude Opus 5.5 | |
|---|---|---|---|
| Status | Internal testing (reported) | Available | Available |
| Model ID on TeamoRouter | none yet | gemini-4-argon |
claude-opus-5-5 |
| Official price, input / output per 1M | not published | $2 / $10 (introductory) | $4 / $20 |
| TeamoRouter, input / output per 1M | — | ≈ $0.58 / $2.91 | ≈ $1.11 / $5.54 |
| Context window | unknown | 1M tokens | 1M tokens |
TeamoRouter prices are at the time of writing and change with upstream; the current numbers are on the pricing page. Google has said the Argon introductory price later rises to $4 / $20 without giving a date.
If you want to know whether Carbon is worth waiting for, the practical test is the one the leak describes: run the coding tasks you care about on Opus 5.5 and on Gemini 4 Argon today with the same key, and compare again the day Carbon appears.
Use Gemini 4 Argon now
Same key and base URL as every other model:
from openai import OpenAI
client = OpenAI(base_url="https://api.teamorouter.com/v1", api_key="YOUR_KEY")
resp = client.chat.completions.create(
model="gemini-4-argon",
messages=[{"role": "user", "content": "Refactor this function to remove the nested loops: ..."}],
)
print(resp.choices[0].message.content)
When Carbon is released, change model to its ID. Gemini-native request format and more examples: Gemini 4 Argon API.
Paying for usage
No subscription: you top up a balance from $5 and pay only for the tokens you use, by card or with USDT, USDC or ETH from any exchange app (how to pay with crypto). The same key works for Gemini, Claude and GPT.
FAQ
Is Gemini 4 Carbon out? No. As of October 22, 2026, it has only been reported as an internal test build.
Is Carbon better than Opus 5.5? Unknown. The only claim is one Google employee saying its coding "feels comparable" to Opus 5.5.
Is Carbon the same as Gemini 4 Argon? Reports disagree. Argon is the Gemini 4 model you can use now; Carbon is a newer internal build that may ship under the Argon name or separately.
Will Carbon be on TeamoRouter? TeamoRouter lists Google models under Google's own IDs. Once it is on the pricing page, change the model name in your request.
Related
- Gemini 4 Argon API: model ID, pricing and request examples
- Claude Opus 5.5 API: the model Carbon is compared to