Test credit card numbers are used within the PayPal Sandbox to validate the authorization, capture, and credit transaction flows.

Because test credit cards don't include a card verification code (CVV), you can use 123 as the CVV for Visa, MasterCard, Discover and Diners Club, or 1234 as the CVV for American Express.

When using test cards, you can specify an expiration date in the future, using one of the following formats:

• PayPal Payments Pro – Use format mmyyyy.
• PayPal Payflow Pro – Use format mmyy.

Use PayPal's Credit Card Generator to generate random credit card information for testing. You can create test versions of Visa, Mastercard, American Express, Discover, Maestro, or JCB credit cards.

You may also use test credit card numbers that are issued within the PayPal Sandbox account. To learn how to get a test credit card within Sandbox, see How do I create a Sandbox test account?  

Not what you're looking for? Try these articles:

How do I Link, Remove, or Update a card?
PayPal Sandbox Testing Guide