2007

Overview
Technical Details
14 April 2007 Name-Value Pair API Developer Guide and Reference
Request Format
Each NVP request consists of required and optional parameters and their values. Parameter
names are not case sensitive. The examples in this document use UPPERCASE for parameter
names and divide the parameters into required security parameters and body parameters.
In practice, you need to concatenate all parameters and values into a single URL-encoded
string. After the METHOD parameter, you can specify the parameters in any order.
Required Security Parameters
The required security parameters are described below. These are your PayPal API credentials.
IMPORTANT: You must protect the values for USER, PWD, and SIGNATURE in your
implementation. Consider storing these values in a secure location other than
your web server document root and setting the file permissions so that only
the system user that executes your ecommerce application can access it.
The sample code does not store these values securely. The sample code
should never be used in production.
TABLE 1.3 General Format of a Request
Required
Security
Parameters
USER=apiUsername&PWD=apiPassword&SIGNATURE=apiSignature
&SUBJECT=optionalThirdPartyEmailAddress&VERSION=2.3
The following parameters are always required:
USER
PWD
VERSION=2.3
N
OTE: The examples show the required security parameters like this:
[requiredSecurityParameters]
Body
Parameters
&METHOD=methodName&otherRequiredAndOptionalParameters
TABLE 1.4 Required Security Parameters: API Credentials
Parameter Value
USER Required Your PayPal API Username.
PWD Required Your PayPal API Password.
VERSION=2.3 Required Version number of the NVP API service.
SIGNATURE Optional Your PayPal API signature string.
If you use an API certificate, do not include this parameter.
SUBJECT Optional Email address of a PayPal account that has granted you permission to
make this call.
Set this parameter only if you are calling an API on a different user’s
behalf.