2009

Table Of Contents
Name-Value Pair API Developer Guide 08 April 2009 11
1
PayPal NVP API Overview
This overview describes the PayPal Name-Value Pair (NVP) API at a high level.
z “Introducing the PayPal NVP API” on page 11
z “Basic Steps” on page 12
z “Taking Your Application Live” on page 13
z “Technical Details” on page 14
Introducing the PayPal NVP API
The PayPal NVP API is a simple programmatic interface that allows you, the merchant, to
access PayPal’s business functionality to:
z Accept PayPal in checkout on your website using Express Checkout.
z Charge a credit card using Direct Payment.
z Capture payments previously authorized through Express Checkout, Direct Payment, or
Website Payments Standard.
z Reauthorize or void previous authorizations.
z Pay one or more recipients using Mass Payment.
z Issue full refunds or multiple partial refunds.
z Search transactions using a start date or other criteria.
z View details of a specific transaction.
The PayPal NVP API makes it easy to add PayPal to your web application. You construct an
NVP string and post it to the PayPal server using HTTPS. PayPal posts back a reponse in NVP
format.
Integrating with the PayPal API
You can develop with the PayPal NVP API using two different approaches:
Integrate Directly
You can integrate directly with the PayPal NVP API using the programming language of your
choice. This is the most straightforward and flexible approach. You can download web
samples that show how to integrate directly using Classic ASP, PHP, and ColdFusion.