2009

PayPal NVP API Overview
Technical Details
16 08 April 2009 Name-Value Pair API Developer Guide
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.
Security Parameters
The security parameters are described below. These are your PayPal API credentials.
Required Security Parameters: 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.
You may see sample code where these values are stored in an HTML form.
The following is an example of what you should NOT do in production:
<form method=post action=https://api-3t.sandbox.paypal.com/nvp>
<!-- UNPROTECTED VALUES. DO NOT USE IN PRODUCTION! -->
<input type=hidden name=USER value=xxxxxx.paypal.com>
<input type=hidden name=PWD value=abcdefg>
<input type=hidden name=SIGNATURE value=xxxxxxxxxxxxxxx>
...
</form>
API Parameters
The request body must contain the name of the API method in the METHOD parameter. In
addition, each method has required and optional parameters:
METHOD=methodName&requiredAndOptionalParameters
Parameter Value
USER (Required) Your PayPal API Username.
PWD (Required) Your PayPal API Password.
VERSION=
<current version> (Required) Version number of the NVP API service, such as 56.0.
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.