--- title: "Gemini 4 Carbon Is Out, and Its API Price Doubles on December 1" description: "Google's Gemini 4 Carbon is out in the API, the Gemini app and AI Mode for Ultra subscribers, and its $2/$10 API price doubles on December 1. Who it's for." url: https://publishmyblog.com/ai/google-releases-gemini-4-carbon/ section: "AI" author: "Saeed Shahriar" published: 2026-11-12T11:49:15.320Z --- # Gemini 4 Carbon Is Out, and Its API Price Doubles on December 1 Google's strongest model is live for paying developers and Ultra subscribers, at a launch price that only lasts three weeks. Google has opened up Gemini 4 Carbon, the model it calls its strongest yet, to paying developers, businesses and Google AI Ultra subscribers. If you build on the Gemini API, write down one date. **The launch price doubles on December 1.** That's under three weeks away. Two weeks ago Carbon only went to cybersecurity defenders in Google's Fairwind Program. Since November 10 you can use Gemini 4 Carbon in the API, the Gemini app, Google Antigravity and AI Mode in Search, [Google DeepMind says](https://deepmind.google/blog/gemini-4-carbon-is-now-available/). ## What Carbon is for Google pitches it for the hardest jobs: long coding and debugging work, deep research, and agents that work through long, multi-step tasks. So should you switch from Argon? Probably not for everything. Here's why. Google itself says **Argon, launched recently, is still the right pick for most software and knowledge work**. Meanwhile, Gemini 4 Carbon spends more tokens thinking and checking its own work, so each answer costs you more, even at the same price per token you pay for Argon. The benchmark claims are Google's own. Grain of salt. It says Carbon ranks first, at less than half the cost per task of the next best outside model, on: - CursorBench 4.0 - Perplexity's WANDR - Zapier's AutomationBench ## Where you can use it Google's rollout: - **Gemini API:** paid tier only, in Google AI Studio, Android Studio and Gemini for business. - Google AI Ultra: the Gemini app, Google Antigravity and AI Mode in Search. - Antigravity: a preview of /swarm, which turns one prompt into a team of agents you can watch work. In Search, **Carbon shows up in the AI Mode model picker for Google AI Ultra subscribers**, [Search Engine Roundtable reports](https://www.seroundtable.com/gemini-4-carbon-google-search-ai-mode-42502.html). Google's Robby Stein said on X it brings "deeper reasoning" to AI Mode. Does that change what people who search for your site see? Only for Google AI Ultra subscribers. That's a paid plan. ## The security angle Carbon's main selling point is **finding and fixing security holes**. Two examples: - Google's researchers used it to prove two bugs in popular open-source software were exploitable, comparable in severity to [PHP2Shell](https://publishmyblog.com/website-tools/php2shell-critical-php-flaws/). A patch is out. - Wiz scanned two big SaaS providers with it and found zero-day flaws in under two hours, Google says. That cuts both ways for you, I think. Defenders get faster, and so might attackers. But you'll likely see more patches to apply, too. ## What we checked On 12 November we read Google's [Gemini API pricing page](https://aistudio.google.com/docs/pricing) for gemini-4-carbon. **It's $2 per million input tokens and $10 per million output tokens through November 30, then $4 and $20 from December 1.** Thinking tokens count as output, and there's no free tier. - Argon has the exact same prices and the same December 1 price increase, so the "introductory price" Google mentions covers both models. - Google's [models page](https://aistudio.google.com/docs/models) lists Carbon with a 1 million token context and text, image, audio, video and PDF input, the same specs it gives Argon. ## Why it matters Who should care this week? Developers. Mostly you, if you run an app, a plugin or an agent on the Gemini API paid tier and you've been waiting for Google's strongest model to land somewhere you can actually use it. My read: test it now. But plan your budget at the December 1 price, because the model you try this month at $2 and $10 will cost you twice that per token once November ends. Of course, a model that thinks longer, at the December 1 price, can more than double your bill. That said, you don't have to pick one model for every job you run through the Gemini API. **Keep Argon, or a lighter model, for your routine calls.** Still doing SEO for your site the usual way? Relax. You don't need to change anything yet. Google hasn't said when, or whether, Carbon reaches all of AI Mode, so most people who meet your site in [Google's AI Mode](https://publishmyblog.com/seo/google-expands-ai-mode-ads/) still get answers from other models for now. Then there's your own stack, if your site runs on open-source software: - Turn on automatic updates where you can. - Read your host's and your plugins' security notices the day they land. Old bugs are getting easier to find. For everyone. ## Common Questions **Is Gemini 4 Carbon free to use?** No. It isn't on the Gemini API free tier, and in Google's consumer apps it's limited to Google AI Ultra subscribers for now. **How much does the Gemini 4 Carbon API cost?** $2 per million input tokens and $10 per million output tokens until November 30, 2026. From December 1, it's $4 per million input tokens and $20 per million output tokens, Google's pricing page says. **What's the difference between Gemini 4 Carbon and Argon?** Carbon is built for the hardest, longest tasks and uses more tokens to reason and check its work, while Google says Argon, at the same price, is still the better fit for most everyday coding and knowledge work. ## Sources - [Gemini 4 Carbon is now available](https://deepmind.google/blog/gemini-4-carbon-is-now-available/), Google DeepMind - [Gemini 4 Carbon is now available for developers.](https://blog.google/innovation-and-ai/technology/developers-tools/gemini-4-carbon-developers/), Google - [Gemini 4 Carbon Now In Google Search AI Mode](https://www.seroundtable.com/gemini-4-carbon-google-search-ai-mode-42502.html), Search Engine Roundtable - [Gemini Developer API pricing](https://aistudio.google.com/docs/pricing), Google AI Studio - [Models](https://aistudio.google.com/docs/models), Google AI Studio