Gemini 4 Carbon: Release Date, Pricing & Access
Explore Gemini 4 Carbon's release timeline, API pricing, access restrictions, and benchmarks, plus comparisons with Gemini 4 Argon and Claude Opus 5.5.
Gemini 4 Carbon: Release Date, Price, Access, and How It Compares to Argon and Opus 5.5
Google announced Gemini 4 Carbon on October 28, 2026. It's Google's newest frontier model, and only two weeks after Gemini 4 Argon. It looks strong on paper. The catch: almost nobody can use it yet.
If you build AI products, here's what's confirmed, what's still unknown, and what you can ship with today.
Quick answer: As of October 31, 2026, Gemini 4 Carbon is not in the Gemini API, AI Studio, or the Gemini app. Google is giving it first to a small group of cyber defenders through its Fairwind Program. Google hasn't given a public release date. Carbon's announced introductory API price is $2 per 1M input tokens / $10 per 1M output tokens, then $4 / $20. If you need to ship now, use Gemini 4 Argon (
gemini-4-argon).
What Is Gemini 4 Carbon?
Google calls Carbon its "strongest model with state-of-the-art cybersecurity and long horizon capabilities" (Google blog). It builds on Gemini 4 Argon and focuses on three areas:
- Long-running agentic engineering. Google says internal teams have seen Carbon "run for days" on multi-step tasks, like root-causing and patching subtle bugs across large codebases.
- Cybersecurity defense. Finding vulnerabilities, checking whether they can be exploited, and patching them.
- Coding and web development. Google reports a +89 Elo jump on WebDev Arena, which puts Carbon at #4 (1768).
Ars Technica's take: Carbon "is essentially a slightly better version of Argon," and it may be a post-training upgrade rather than a whole new model (Ars Technica).
Gemini 4 Carbon Release Date: Who Can Use It Now?
Announced: October 28, 2026
Reuters, The Verge, and Ars Technica all covered the announcement on October 28, 2026 (Reuters via Investing.com, The Verge).
Current access: cyber defenders only
Google's rollout plan, in its own words:
- "Starting this week, we will make Carbon available to a subset of cyber defenders"
- Then "gradually phase access to additional trusted partners through our Fairwind Program"
- Then make it available "to developers, businesses, and consumers via our product surfaces as soon as possible"
Google is also taking part in the U.S. government's voluntary pre-release model testing process.
Public release date: not announced
Google has not given a date for developers or consumers. When we checked the Gemini API release notes on October 31, 2026, there was no Carbon entry and no Carbon model ID.
What history suggests (not a promise): Argon followed the same path. Google announced it on September 30, 2026 for Fairwind cyber defenders only, then made it generally available on October 13, 2026. That's about two weeks. Ars Technica says Carbon "could be available in a couple of weeks" if it follows Argon, and will "probably" reach AI Ultra subscribers and Gemini API developers first. Treat both points as informed guesses, not dates.
Gemini 4 Carbon Price
| Input (per 1M tokens) | Output (per 1M tokens) | Cached input | |
|---|---|---|---|
| Introductory price | $2 | $10 | 95% off input |
| After intro period | $4 | $20 | — (not specified) |
Source: Google's announcement.
Things to know before you budget:
- The intro period has no end date. Argon's intro pricing ends November 30, 2026 (Gemini API docs). Google declined to give Ars Technica an end date for Carbon.
- The price is announced, but you can't pay it yet. You can't call Carbon, so no one is billed at this rate today.
- Thinking tokens count. For Argon, output pricing includes thinking tokens (docs). Expect the same for Carbon, but Google hasn't confirmed it.
Gemini 4 Carbon Benchmarks
All numbers below are Google's own figures from the launch post. Google says the cybersecurity benchmarks were run without guardrails.
| Benchmark | What it measures | Gemini 4 Carbon |
|---|---|---|
| Artificial Analysis Intelligence Index v5.0 | Overall intelligence (composite) | 59 (#1) |
| SEC-bench Pro | Finding real vulnerabilities | 88.2% |
| ExploitGym | Validating exploitability | 54.8% |
| CWE-bench (Collinear) | Patching at the root cause | 71.0% |
| WebDev Arena | Web dev quality (Elo) | 1768 (#4, +89) |
| Gray Swan Indirect Prompt Injection | Attack success rate (lower is better) | 0.0% |
| Terminal-Bench 4.0 | Successful cheating rate | 0.0% (attempts: 0.4%) |
Google also says Carbon:
- has more than a 2x higher success rate at generating secure code than Argon (internal benchmark)
- makes about 2x fewer unsupported claims than Argon
- cut overreach by 26% and under-service by 29%
Ars Technica's caveat: "every frontier model scores in the same neighborhood in these tests. The gap between Carbon and the competition is just a few points." No independent lab has published hands-on results yet, because no one outside the early group has access.
Gemini 4 Carbon vs Gemini 4 Argon
| Gemini 4 Carbon | Gemini 4 Argon | |
|---|---|---|
| Announced | Oct 28, 2026 | Sep 30, 2026 |
| Generally available | Not yet | Oct 13, 2026 |
| Who can use it | A subset of cyber defenders, then Fairwind partners | Paid Gemini API, AI Studio, Google Cloud; AI Pro and Ultra in the Gemini app |
| Model ID | Not published | gemini-4-argon |
| Intro API price | $2 / $10 per 1M | $2 / $10 per 1M |
| Standard API price | $4 / $20 per 1M | $4 / $20 per 1M (from Dec 1, 2026) |
| Intro period ends | Not announced | Nov 30, 2026 |
| Context window | Not published | 1M tokens, unified input and output |
| Prompt-injection attack success (Gray Swan IPI) | 0.0% | 0.7% |
Sources: Carbon announcement, Argon GA post, What's new in Gemini 4 Argon.
Bottom line: at list price they cost the same, and Carbon wins on Google's tests by small margins. Today, though, only Argon can actually run in production.
Gemini 4 Carbon vs Claude Opus 5.5
People are searching for this comparison a lot. Here's what's verifiable:
| Gemini 4 Carbon | Claude Opus 5.5 | |
|---|---|---|
| Can developers use it? | No (limited access) | Yes, claude-opus-5-5 |
| API price (input / output per 1M) | $2 / $10 intro, then $4 / $20 | $4 / $20 |
| Context window | Not published | 1M tokens |
| Gray Swan prompt-injection attack success | 0.0% | 1% |
Sources: Claude Opus 5.5 docs, Ars Technica.
On benchmarks, Ars Technica reports that Google's charts show Carbon beating GPT-6 Astra, Claude Opus 5.5, and Claude Fable 5.1 "in almost every test," by a few points. The Verge notes that Opus 5.5 and GPT-6 Astra trail Carbon on the Artificial Analysis Intelligence Index v5.0. These are vendor-published comparisons. Wait for independent tests before you switch a production workload.
What Builders Can Do Right Now
- Build on Gemini 4 Argon today. It costs the same as Carbon and is already GA. If Carbon follows Argon's path, moving over later may just mean changing the model ID. That's an assumption until Google publishes Carbon's ID and docs.
- Plan for the price change. Argon's intro price ends November 30, 2026, and the standard rates are double. Run your cost estimates at $4 / $20, not $2 / $10.
- If you work in cybersecurity, the route to early access is Google's Fairwind Program. Google's Argon launch post invited cyber defenders to apply. Google hasn't published a separate application for Carbon.
- Ignore third-party "Carbon model IDs" and prices until Google lists them on its own pricing page or release notes.
- Building a tool on top of Gemini? Submit it to Submito so makers and early adopters can find it.
FAQ
When is the Gemini 4 Carbon release date?
Google announced it on October 28, 2026. Access started that week for a subset of cyber defenders. Google hasn't announced a public release date for developers or consumers, only "as soon as possible."
Can I use Gemini 4 Carbon in the Gemini app or API?
Not yet. As of October 31, 2026, Carbon isn't in the Gemini API release notes and has no public model ID. Gemini 4 Argon is the model you can use now.
How much does Gemini 4 Carbon cost?
The introductory price is $2 per 1M input tokens and $10 per 1M output tokens, with cached input 95% off. After the intro period it's $4 and $20. Google hasn't said when the intro period ends.
What's the difference between Gemini 4 Carbon and Argon?
Carbon builds on Argon. Google says it's stronger at cybersecurity, long-running agentic tasks, and secure code, and wins Google's benchmarks by small margins. Both have the same announced prices. Argon is generally available; Carbon isn't.
Is Gemini 4 Carbon better than Claude Opus 5.5?
On Google's published benchmarks, Carbon edges out Opus 5.5 in almost every test, by a few points (per Ars Technica). There are no independent hands-on comparisons yet. Opus 5.5 is available now at $4 / $20 per 1M tokens.
What is the Fairwind Program?
It's Google's access program for cybersecurity defenders. Google used it for Argon's early access and is using it now for Carbon. Google's Argon post invited cyber defenders to apply. Google hasn't published a separate route for Carbon.
Final Thoughts
Gemini 4 Carbon is a clear signal of where frontier models are heading: longer-running agents, security work, and safer code. Right now it's an announcement for most people, not a product. Build on Argon, budget for the post-November price, and keep an eye on Google's release notes. If Argon's two-week path repeats, Carbon could arrive soon, but Google hasn't promised a date.
Facts checked on October 31, 2026. We'll update this page when Google publishes Carbon's public availability, model ID, or intro-period end date.