Vertex AI in express mode overview

With Vertex AI in express mode, you can quickly sign up and begin building generative AI applications on Google Cloud. This simplified setup experience streamlines access to Google Cloud APIs by simplifying organization, billing, and project management.

To learn more about Vertex AI in express mode, see Google Cloud express mode FAQs.

Sign up for express mode

Vertex AI is available in express mode for developers with a @gmail.com Google Account, regardless of whether they are new or existing Google Cloud users:

  • New users: New users to Google Cloud can sign up for an express mode account in a free tier to try Vertex AI for free for up to 90 days, within the specified quotas. You don't need to provide billing information to sign up in the free tier. You can upgrade to a paid tier by adding a billing account.

    Vertex AI in express mode is separate from, and not available through, the Google Cloud Free Program. If you are in the Google Cloud Free Program, see the other quickstarts in the Get Started section to start using Generative AI on Vertex AI.

  • Existing users: If you're an existing Google Cloud user, you can also use Vertex AI directly in express mode. In this case, you sign up for the paid tier and can use your existing billing account. With express mode, you can still use any existing credits on your account.

To sign up for Vertex AI in express mode, access Express Mode from the Google Cloud console:

Go to Express Mode

After you're set up, you can start using Vertex AI in express mode by following one of the tutorials:

Learn about Vertex AI in express mode

When you sign up for express mode, Google Cloud enables APIs on your behalf. This process happens in the background, so you can start using Vertex AI without needing to manually configure resources.

When you sign up for express mode, you get access to the following:

  • Core Vertex AI Studio features. Quickly test and customize prompts for different generative AI models, and get the corresponding code to use in your application.
  • An API key. Authenticate fast from your application.
  • Free tier for new Google Cloud users during 90 days. During the 90 day limit of the free tier for new Google Cloud users, you can use the Vertex AI APIs that support express mode for free, up to their quotas. You don't have to provide billing information. You can increase your quota limits at any time by enabling billing.

If you are an existing Google Cloud user or after enabling billing, the 90 day free tier is removed. You transition to a paid tier to access extended quota limits and additional Google Cloud features. As your quotas are increased, you only pay for what you use. At any time, you can choose to end express mode and start using all the Google Cloud services and capabilities.

The following table lists the differences between the express mode experiences and the full Vertex AI experience:

Item Vertex AI express mode in the free tier Vertex AI express mode in the paid tier Full Vertex AI
Time limit 90 days Unlimited Unlimited
Available services Basic Generative AI on Vertex AI services. Expanded Vertex AI services and select Google Cloud services. All Google Cloud services, including Vertex AI.
Data sources Google Drive
  • Google Drive
  • Web files
  • YouTube video URLs
 All data sources available in Google Cloud.
Quota Free tier limits. See Available models and rate limits in express mode. Standard pay-as-you-go limits. See Rate limits. Standard pay-as-you-go limits. See Rate limits.
Service level agreement (SLA) None Vertex AI SLA Vertex AI SLA
Standard format of API endpoints Specify API key instead of project ID and location. For example:
https://aiplatform.googleapis.com/v1/publishers/google/models/{model}:streamGenerateContent?key={API_KEY} 		Specify API key instead of project ID and location. For example:
https://aiplatform.googleapis.com/v1/publishers/google/models/{model}:streamGenerateContent?key={API_KEY} 		Specify project ID and location. For example:
https://{location}-aiplatform.googleapis.com/v1/projects/{project}/locations/{location}/publishers/google/models/{model}:streamGenerateContent

Available models and rate limits in express mode

You can try out several models in express mode, including the Gemini 2.0 Flash models. The following table lists the models that are available in express mode, along with their rate limits:

Model category Available models Requests per minute Discontinuation date
Gemini gemini-2.5-flash-lite 10 July 22, 2026
gemini-2.5-pro 10 June 17, 2026
gemini-2.5-flash 10 June 17, 2026
gemini-2.5-flash-image-preview 10 -
gemini-2.5-flash-lite-preview-06-17 10 August 14, 2025
gemini-2.0-flash-001 10 February 5, 2026
gemini-2.0-flash-lite-001 10 February 25, 2026

For Gemini 2.0 models, the Multimodal Live API isn't available in the Google Cloud console in express mode. To use the Multimodal Live API in express mode, use the Vertex AI API or the Google Gen AI SDK.

Vertex AI in express mode workflow

You can start sending requests from your application to Vertex AI APIs in three steps:

  1. After signing up for express mode, use Vertex AI Studio to quickly try Vertex AI features:

    Go to Vertex AI Studio

    For example, select Vertex AI Studio > Create prompt to create and optimize multimodal prompts using a variety of Gemini models.

  2. Get the code for what you implemented with the UI.

    On the prompt page, click Build with code > Get code. A panel opens showing code that programmatically sends the same requests that you implemented in the UI. You can get the code for a programming language or curl. You can use Google Colab to try the Python code.

  3. Use your API key to authenticate with the Vertex AI API.

    In Google Cloud console in express mode, open APIs & Services > Credentials:

    Go to Credentials

    Then, copy your Generative Language API Key into your code where it says "YOUR_API_KEY". For example:

    Python

    The Google Gen AI SDK for Python is available on PyPI and GitHub:

    To learn more, see the Python SDK reference (opens in a new tab). 

    from google import genai

# TODO(developer): Update below line
API_KEY = "YOUR_API_KEY"

client = genai.Client(vertexai=True, api_key=API_KEY)

response = client.models.generate_content(
    model="gemini-2.5-flash",
    contents="Explain bubble sort to me.",
)

print(response.text)
# Example response:
# Bubble Sort is a simple sorting algorithm that repeatedly steps through the list

What's different in express mode

Vertex AI in express mode provides a subset of the features for Generative AI on Vertex AI. Therefore, some of the Vertex AI documentation is not relevant if you signed up in express mode. For details on the available API endpoints in express mode, see the Vertex AI in express mode REST API reference.

In addition, customers in Google Cloud typically use organizations and projects to work with resources (for example, to call an API endpoint). When using Vertex AI in express mode, you don't need to worry about organizations or projects. However, you might see them mentioned in some of the Google Cloud documentation that you reference while you're using Vertex AI in express mode. You can still use the documentation, but ignore concepts and instructions that refer to organizations and projects. In addition, the location you selected when signing up in express mode is used throughout your experience.

When calling REST API endpoints in express mode, you'll use the endpoint format for express mode and specify your API key. For example:

Standard endpoint URL https://{location}-aiplatform.googleapis.com/v1/projects/{project}/locations/{location}/publishers/google/models/{model}:streamGenerateContent
Endpoint URL in express mode https://aiplatform.googleapis.com/v1/publishers/google/models/{model}:streamGenerateContent?key={API_KEY}

View and manage API keys

To authenticate with Vertex AI API endpoints that support express mode, use the API key that was created for you during sign-up or any key that you've created in express mode. An API key is an encrypted string that is auto-generated for you when you sign up in express mode. These API keys can be viewed and managed on the APIs & Services page.

To learn more about the best practices for managing API keys, see Best practices for managing API keys.

To view and manage your API keys, do the following:

  1. In the Google Cloud console, go to the Credentials page:

    Go to Credentials

  2. In the API Keys section, you can manage your API keys.

View quotas

Your free use of Vertex AI in express mode is restricted by quotas. These quotas restrict the rate at which you can use Vertex AI in express mode at no cost. A quota limits how much of a Google Cloud resource you can use.

To view your current usage and quotas, do the following:

  1. Go to the Vertex AI Studio Overview page in express mode.

    Go to Vertex AI Studio

  2. In Google Cloud console in express mode, open Quotas & System Limits:

    Go to Quotas & System Limits

  3. Explore your service quotas.

Enable and manage billing

You can increase your quotas and remove the 90 day limit by enabling billing.

After enabling billing, you pay only for what you use. You can also save your prompts and access additional settings in the Google Cloud console that are that grayed out when billing isn't enabled.

To manage billing, do the following:

  1. Go to the Vertex AI Studio Overview page in express mode.

    Go to Vertex AI Studio

  2. In Google Cloud console in express mode, open Billing:

    Go to Billing

  3. Manage your billing accounts.

Start using all Google Cloud capabilities and services

Express mode is designed to help you get started quickly. When you're ready to use other Google Cloud services or need more control over your environment, you can transition your express mode account to a standard Google Cloud account. This process is sometimes called upgrade.

You can start using all the capabilities and services available in Google Cloud in your project by upgrading your express mode account.

To upgrade from express mode, do the following:

  1. Go to the Vertex AI Studio Overview page in express mode.

    Go to Vertex AI Studio

  2. In Google Cloud console in express mode, open Billing:

    Go to Billing

  3. In the Access all Google Cloud section, click Learn more and get started.

After you upgrade from express mode, specify your project ID and location instead of your API key when you call the REST API endpoints. For example:

https://{location}-aiplatform.googleapis.com/v1/projects/{projectid}/locations/{location}/publishers/google/models/{model}:streamGenerateContent

What's next