> ## AI Agent Context
> Get the complete documentation index at: https://aistudio.google.com/llms.txt
> Use this file to discover all available pages.
> For the full documentation in a single file, fetch: https://aistudio.google.com/llms-full.txt

# Google AI plans

Use your Google AI subscription plan in AI Studio.

Google AI Pro and Ultra subscription plans provide greater model access and
increased rate limits in AI Studio. Compared to the Free plan, these plans offer
more resources for prototyping and development.

To sign up for a Google AI plan, upgrade in Google AI Studio. Click **Upgrade**
in the left menu. You can also sign up on the
[Google AI Plans page](https://one.google.com/about/google-ai-plans/).

## Overview  {% id="overview" %}

Google AI Pro and Ultra subscriptions unlock paid models and higher rate
limits. These benefits apply to the Google AI Studio Playground and features
like the Code Assistant in [Build mode](/docs/aistudio-build-mode) for rapid
prototyping. Subscribers get baseline daily quota allowances higher than the
Free plan for use across the
[Playground](https://aistudio.google.com/prompts/new_chat) and
[Build](https://aistudio.google.com/apps) interfaces. Daily limits use resets
rather than rolling time windows. This provides a consistent development
experience before you transition to production with Cloud Billing.

| Plan | AI Studio usage | Model access and benefits |
| :--- | :--- | :--- |
| **Free** | Modest quota | Basic limits and access, including [Gemini 4 Hydrogen](/docs/models/gemini-4-hydrogen), with the option to upgrade for more. |
| **AI Pro** | Higher quota | Access to premium models like [Gemini 4 Argon](/docs/models/gemini-4-argon), Gemini Pro, [Gemini Nano Banana 2.1](/docs/models/gemini-nano-banana-2.1), and [Lyria 3.5](/docs/models/lyria-3.5). |
| **AI Ultra** | Highest quota | Highest limits for prototyping, development, and advanced frontier models like [Gemini 4 Carbon](/docs/models/gemini-4-carbon) and [Gemini 4 Argon](/docs/models/gemini-4-argon). |

## Gemini API usage  {% id="gemini-api-usage" %}

When you reach your daily subscription quota in AI Studio, you can continue
working by using a Gemini API key. Enable Cloud Billing to pay per request for
Gemini API usage. You can track Gemini API usage for projects and API keys in
the [AI Studio Dashboard](https://aistudio.google.com/projects).

Subscribers with Google Cloud projects and Cloud Billing enabled can get
monthly Cloud credits from the
[Google Developer Program](https://developers.google.com/program). These
credits apply to Cloud services, including the Gemini API. Prepay and postpay
usage and billing remain unchanged. With prepay billing, you need a paid
balance greater than $0 in AI Studio to activate promotional credits. Google
applies eligible Google Cloud credits first.
[Learn more](/docs/billing#billing-plans).

Google AI subscriptions help you start advanced experimentation, learning, and
development. To get started with app building and prototyping at scale, use a
[Starter Tier project](https://docs.cloud.google.com/docs/starter-tier) (if
eligible) or a Google Cloud project with Gemini API keys.

## Limitations and compatibility  {% id="limitations" %}

*   **AI Studio UI only:** Google AI plan benefits for developer usage apply only within the Google AI Studio web interface. Google bills and manages Gemini API usage (such as using API keys or external applications) separately. You can, however, use your subscription across other Google products (see [Google AI Plans](https://one.google.com/about/google-ai-plans/)).
*   **Different from API billing:** Google AI plans for AI Studio are separate from [Gemini API usage tiers](/docs/billing), which cover development and production API usage.
*   **Google One credits:** [Google One AI credits](https://support.google.com/googleone/answer/16287445) are a separate credit system that isn't supported within AI Studio and don't overlap with Google Cloud credits.
*   **Gemini 4 access:** [Gemini 4 Hydrogen](/docs/models/gemini-4-hydrogen) is available on all plans, including the Free plan. [Gemini 4 Carbon](/docs/models/gemini-4-carbon) requires an AI Ultra plan in AI Studio (not available on the Free or AI Pro plans). [Gemini 4 Argon](/docs/models/gemini-4-argon) is available on AI Pro and AI Ultra (not available on the Free plan).
*   **Agent access:** Google AI plans don't include access to agents like Deep Research or Antigravity Preview. These features require a [paid API key](/docs/billing#setup-billing).

## What's next  {% id="whats-next" %}

*   Learn more about [AI Studio Build mode](/docs/aistudio-build-mode).
*   Learn more about [Starter Tier](https://docs.cloud.google.com/docs/starter-tier).
*   Understand [Gemini API billing and usage tiers](/docs/billing).
*   Explore available [Gemini models](/docs/models).