Before you start accepting live payments on your calculator, we strongly recommend to test your PayPal button and to make sure that it works correctly. Follow the steps below for information how to set up your payment button for testing, and how to test it using PayPal Sandbox environment.
You get two PayPal test accounts by default - business and personal. To test a typical PayPal transaction, you'll need to use both types of accounts. You can create more test accounts by clicking Create account button at the top-right cornet. Use these accounts for your calculator's payment button testing. All sandbox transactions are tracked on the Sandbox test site — https://www.sandbox.paypal.com.
See PayPal Sandbox Testing Guide (paypal.com) for more information.