PayPal Classic APIs provide a set of application programming interfaces (APIs) that let you add PayPal payment and transaction functionality to your business applications. The Classic APIs offer interfaces that cover all aspects of complex business transactions, including invoicing services, notifications, subscription services, parallel payments, permissions services, and functionality to processes refunds.
To help you quickly integrate PayPal transaction processes into your business flows, PayPal provides both SDK tools and code sample code. Visit the Developer Welcome page to see the complete set of PayPal API products and services.
The PayPal development life cycle
The high-level development life cycle is the same for all PayPal services. You incorporate PayPal transaction functionality into applications as follows:
- Register as a PayPal Developer.
- Integrate PayPal functionality to your website and mobile applications.
- Test your PayPal transaction routines.
- Go live with your application.
- Maintain and upgrade your app.
The PayPal developer process
Here's how you code, test, and deploy your PayPal applications:
- Register as a PayPal Developer on the Developer website.
- Familiarize yourself with how to make PayPal API calls, as described in the PayPal APIs Getting Started Guide.
- Create virtual test accounts in the Sandbox, as described in the Testing Classic API Calls.
- Use the correct endpoints and credentials for the environment and operations you're addressing.
- Refer to the integration documentation for guidance. You can also utilize the Express Checkout and Payflow Integration Wizard.
- Test your PayPal routines using the Sandbox.
- Take your application Live, as outlined in Going Live with Your Application.
Development process and policy docs
The following docs address the different phases of development and outline the PayPal developer policies:
- Policies and guidelines
- Development process
Visit the Support page on the PayPal developer site for support resources and additional information.