Circle APIs Documentation

Learn how to integrate with Circle APIs to accept traditional and USDC payments, automate payouts, embed digital dollar accounts into your product or service, or power your internet marketplace.

Sample Payments Application

We have built a sample web application to demonstrate the use of Circle Payments API. You can clone the Github repository, configure the app and run it locally. The sample web application's source code is available at

API key

Before you start, you should make sure you have an API key on the sandbox environment. If you haven't yet created a sandbox account, follow the steps on the getting started guide.

Once you have generated your API key, enter it on the settings tab on the top right corner of the sample application.

Install and configure the sample application

You can clone the sample payments application Github repository, configure it and run it locally in just a few steps.


If you don't already, make sure you have npm and yarn installed.

# Clone the sample app Github repository
git clone

# Change into the sample app folder
cd payments-sample-app

# Create a .env file and configure the base url for api calls
echo BASE_URL= > .env

# Install the dependencies
yarn install

Run the sample application locally

To run the sample application locally, execute the following command.

# Run the sample app locally
yarn dev
The sample application should now be running at: http://localhost:3011.


Take the API key you generated earlier, and enter it on the settings tab on the top right corner of the sample application.

Sample Flows

The sample web application has two broad sections, accessible via the left menu. The first one is the Sample Flows section, where you have example screens for the basic Circle Payments API operations such as creating a card and making a payment.

API Viewer

The second section is the API Viewer section, where you can quickly input some parameters and inspect the request and response payloads being exchanged with the Circle Payments API. This is typically useful to understand the various endpoints and schemas before you jump straight into coding your own server side integration.

Updated 9 months ago

Sample Payments Application

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