Getting started

How PayPal Checkout works

Integrate PayPal Checkout to give your customers payment buttons for PayPal, Venmo, debit, and credit cards.

PayPal's JavaScript SDK supports how you want to accept payments on your website. Our SDK handles displaying the buttons for PayPal and other payment methods, so your customers can pay with whatever method they choose. They can also use a pre-built form to pay directly using credit or debit.

Checkout

PayPal Checkout helps you get set up quickly to accept PayPal and other payment methods. With expanded checkout you can customize the checkout to match your site's branding.

Integration Guide

Implement PayPal Checkout server-side using Node.js, Python, and more.

API Reference

Use the Orders API to create, update, authorize, and capture orders.

JavaScript SDK Reference

Dynamically expose objects and methods based on the components you select.

Integrating the Checkout client

The JavaScript payload shows up in the global window object under the paypal namespace, so you can access it anywhere in your app to render any component in the JavaScript SDK.

The <script> tag fetches the PayPal SDK when your checkout page renders.
When your customer clicks on a PayPal button, the createOrder callback tells your server to initiate an order with PayPal's server.
PayPal server sends the Order ID to your server, which then relays it to the SDK's createOrder callback, prompting the SDK to launch the checkout window for the Order ID.
The customer logs in using PayPal credentials and uses the order review page to verify order details and check out.
The onApprove callback launches after payment is confirmed.
You can use the response to verify the payment was completed or catch any errors about their payment method.

The PayPal buttons component shows up on your website based on the configuration you set in the JavaScript SDK. Your buyer can choose how to check out based on the eligible payment methods. A buyer following the PayPal Checkout flow sees the PayPal, Venmo, and Debit or Credit Card buttons.

When your buyer selects a payment method:

A pop-up shows up on the buyer's screen.
If the buyer is logged into their PayPal account, the pop-up includes details about their order.
This screen shows the buyer's default shipping address and the default shipping option you selected in the initial Orders API call.
The buyer can choose a different shipping address and payment method.
The buyer confirms that all the information is correct.
The buyer selects Complete Purchase to authorize the payment.
The order goes to PayPal's servers, where we process the payment.

Set up your development environment

Build the server

This sample Node.js integration uses the npm package manager. Enter:

npm install

to run the sample application. For more information, visit npm's documentation.

Install dependencies

Set up your integration by running:

npm install @paypal/[email protected] dotenv express body-parser

to install the following 4 libraries at the same time:

@paypal/[email protected] – The PayPal Server SDK provides integration access to the PayPal REST APIs
dotenv – separates your configuration and code by loading environment variables from a .env file into process.env
express – is a Node.js web application framework that supports web and mobile applications
body-parser – is used to parse incoming request bodies in a middleware before your handlers

This sample integration uses PayPal's Server SDK v1.0.0. For more details, visit the PayPal Server SDK documentation (login required).

Verify `package.json`

The following code sample shows a package.json file for a PayPal integration. Replace YOUR-SERVER-NAME.js with the name of your server file in main and start on lines 5 and 8:

{  
  "name": "paypal-checkout-integration-backend-node",  
  "version": "1.0.0",  
  "private": true,  
  "type": "module",  
  "dependencies": {  
    "@paypal/paypal-server-sdk": "^1.0.0",  
    "body-parser": "^1.20.3",  
    "dotenv": "^16.3.1",  
    "express": "^4.18.2"  
  },  
  "scripts": {  
    "server-dev": "nodemon server.js",  
    "start": "npm run server-dev",  
    "prod": "node server.js",  
    "format": "npx prettier --write **/*.{js,jsx,md}",  
    "format:check": "npx prettier --check **/*.{js,jsx,md}"  
  },  
  "devDependencies": {  
    "concurrently": "^8.2.1",  
    "nodemon": "^3.0.1"  
  }  
}

If you're having trouble with your app, reinstall your local library and package files using npm install. If you're getting the following node error, include "type": "module" in your package.json file. This line isn't automatically added when package.json is created.

Warning: To load an ES module, set "type": "module" in the package.json file or use the .mjs extension. Use node --trace-warnings ... to show where the warning was created. See line 5 of the sample package.json file for an example.

Set up environment variables

Update your operating system's local working environment variables to pass your app's client ID and client secret securely. The following examples show how to set up these environment variables in PowerShell on Windows, as well as the Linux and MacOS operating systems:

Windows (PowerShell):

$env:PAYPAL_CLIENT_ID = "<PAYPAL_CLIENT_ID>"
$env:PAYPAL_CLIENT_SECRET = "<PAYPAL_CLIENT_SECRET>"

Linux / MacOS:

export PAYPAL_CLIENT_ID="<PAYPAL_CLIENT_ID>"
export PAYPAL_CLIENT_SECRET="<PAYPAL_CLIENT_SECRET>"

Build the server

The sample Java integration uses the Maven package manager.

Run mvn clean install to build the server. Enter mvn spring-boot:run to start the sample application. For more information, visit Java's documentation.

Install dependencies

This sample integration uses PayPal's Server SDK v1.0.0. For more details, visit the PayPal Server SDK documentation by logging in to your account.

Verify `pom.xml`

The following code sample shows how to set up a pom.xml file for a PayPal integration:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.3.2</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.paypal.sample</groupId>
    <artifactId>advanced-integration</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>PayPal Checkout Integration</name>
    <description>Sample Java demo application for PayPal JS SDK Integration</description>
    <url/>
    <licenses>
        <license/>
    </licenses>
    <developers>
        <developer/>
    </developers>
    <scm>
        <connection/>
        <developerConnection/>
        <tag/>
        <url/>
    </scm>
    <properties>
        <java.version>21</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>
                com.paypal.sdk
            </groupId>
            <artifactId>
                paypal-server-sdk
            </artifactId>
            <version>
                1.0.0
            </version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
             </plugin>
        </plugins>
    </build>
</project>

Set up environment variables

Windows (powershell)
    $env:PAYPAL_CLIENT_ID = "<PAYPAL_CLIENT_ID>"
    $env:PAYPAL_CLIENT_SECRET = "<PAYPAL_CLIENT_SECRET>"
Linux / MacOS
    export PAYPAL_CLIENT_ID="<PAYPAL_CLIENT_ID>"
    export PAYPAL_CLIENT_SECRET="<PAYPAL_CLIENT_SECRET>"

Build the server

This sample PHP integration uses the Homebrew package manager and Composer.

To install composer on macOS, run the command brew install composer. For Windows users, Composer can be downloaded from their website.

Use composer start to run the sample application. For more details, visit composer's documentation.

Install dependencies

Run composer install to add the dependencies you need to set up your PHP integration.

This sample integration uses PayPal's Server SDK v1.0.0. For more details, visit the PayPal Server SDK documentation by logging in to your account.

Verify `composer.json`

The following code sample shows a composer.json file for a PayPal integration:

{
    "description": "PayPal JS SDK Integration - Checkout Flow",
    "license": "MIT",
    "require": {
        "php": "^7.4 || ^8.0",
        "ext-json": "*",
        "paypal/paypal-server-sdk": "1.0.0"
    },
    "require-dev": {
    },
    "scripts": {
        "start": "php -S localhost:8080 -t src"
    },
    "config": {
    }
}

Set up environment variables

Windows (powershell)
    $env:PAYPAL_CLIENT_ID = "<PAYPAL_CLIENT_ID>"
    $env:PAYPAL_CLIENT_SECRET = "<PAYPAL_CLIENT_SECRET>"

Linux / MacOS
    export PAYPAL_CLIENT_ID="<PAYPAL_CLIENT_ID>"
    export PAYPAL_CLIENT_SECRET="<PAYPAL_CLIENT_SECRET>"

Build the server

This sample Python integration uses the Flask package manager.

Run python3 -m venv .venv to build the server. Enter flask --app server run to start the sample application.

Install dependencies

Run pip install -r requirements.txt to add the dependencies you need to set up your Python integration.

This sample integration uses PayPal's Server SDK v1.0.0. For more details, visit the PayPal Server SDK documentation by logging in to your account.

Verify requirements

The following code sample shows a requirements.txt file for a PayPal integration:

Flask==3.0.3
paypal-server-sdk==1.0.0

Set up environment variables

Windows (powershell)
    $env:PAYPAL_CLIENT_ID = "<PAYPAL_CLIENT_ID>"
    $env:PAYPAL_CLIENT_SECRET = "<PAYPAL_CLIENT_SECRET>"
    
Linux / MacOS
    export PAYPAL_CLIENT_ID="<PAYPAL_CLIENT_ID>"
    export PAYPAL_CLIENT_SECRET="<PAYPAL_CLIENT_SECRET>"

Build the server

This sample Ruby integration uses the Sinatra package manager.

Enter bundle exec ruby server.rb to run the sample application.

Install dependencies

Run bundle install to add the dependencies you need to set up your Ruby integration.

This sample integration uses PayPal's Server SDK v1.0.0. For more details, visit the PayPal Server SDK documentation by logging in to your account.

Verify Gemfile

The following code sample shows the Gemfile for a PayPal integration:

# frozen_string_literal: true

source "https://rubygems.org"

gem "paypal-server-sdk", "~> 1.0.0"
gem "puma", "~> 6.4"
gem "rackup", "~> 2.1"
gem "sinatra", "~> 4.0"
gem "sinatra-contrib", "~> 4.0"

Set up environment variables

Windows (powershell)
    $env:PAYPAL_CLIENT_ID = "<PAYPAL_CLIENT_ID>"
    $env:PAYPAL_CLIENT_SECRET = "<PAYPAL_CLIENT_SECRET>"
    
Linux / MacOS
    export PAYPAL_CLIENT_ID="<PAYPAL_CLIENT_ID>"
    export PAYPAL_CLIENT_SECRET="<PAYPAL_CLIENT_SECRET>"

Build the server

This sample .NET integration uses the dotnet package manager.

Run dotnet restore to build the server. Enter dotnet run to start the sample application. For more information, visit .NET's documentation.

Install dependencies

This sample integration uses PayPal's Server SDK v1.0.0. For more details, visit the PayPal Server SDK documentation by logging in to your account.

Verify `.csproj` file

The following code sample shows a PayPalCheckoutIntegration.csproj file for a PayPal integration:

<Project Sdk="Microsoft.NET.Sdk.Web">
    <PropertyGroup>
        <TargetFramework>net8.0</TargetFramework>
        <RootNamespace>PayPalCheckoutIntegration</RootNamespace>
    </PropertyGroup>
    <ItemGroup>
        <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="7.0.9" />
        <PackageReference Include="PayPalServerSDK" Version="1.0.0" />
    </ItemGroup>
</Project>

Set up environment variables

Windows (powershell)
    $env:PAYPAL_CLIENT_ID = "<PAYPAL_CLIENT_ID>"
    $env:PAYPAL_CLIENT_SECRET = "<PAYPAL_CLIENT_SECRET>"
    
Linux / MacOS
    export PAYPAL_CLIENT_ID="<PAYPAL_CLIENT_ID>"
    export PAYPAL_CLIENT_SECRET="<PAYPAL_CLIENT_SECRET>"

View your client ID and client secret in the PayPal Developer Dashboard under Apps & Credentials.

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How PayPal Checkout works

Checkout

Integrating the Checkout client

Set up your development environment

Build the server

Install dependencies

Verify package.json

Set up environment variables

Build the server

Install dependencies

Verify pom.xml

Set up environment variables

Build the server

Install dependencies

Verify composer.json

Set up environment variables

Build the server

Install dependencies

Verify requirements

Set up environment variables

Build the server

Install dependencies

Verify Gemfile

Set up environment variables

Build the server

Install dependencies

Verify .csproj file

Set up environment variables

Verify `package.json`

Verify `pom.xml`

Verify `composer.json`

Verify `.csproj` file