Testing with Fat Zebra

We want to help ensure that going live with your website is a painless and stress free process.

To help reassure you we have built a fully featured sandbox environment designed to replicate the live system entirely - the only difference is no money changes hand. Fat Zebra also provides a set of test card numbers you can use to test your integration completely.

How do I test my website with Fat Zebra?

When you are registered with Fat Zebra you will be provided with a Test Account, which includes its own username and token. Using these details will ensure that transactions are not sent to your live merchant facility but allow you to do a full end-to-end test from your site to our service.

Testing with variable cards will generate a response based on the cent-amount of the transaction - for example if the transaction amount is $100.51 (10051) then the response code will be 51 - Expired Card, and a transaction with the amount $200.00 (20000) will have the response code 00 - Approved.

Card Numbers

These card numbers are valid for use with Fat Zebra:

Type Number Expiry CVV Amount Response
MasterCard 5123 4567 8901 2346 05/2023 123 Any Approved
MasterCard 5313 5810 0012 3430 05/2023 123 Any Declined
MasterCard 5555 5555 5555 4444 05/2023 123 Varying Depends on cent amount
VISA 4005 5500 0000 0001 05/2023 123 Any Approved
VISA 4557 0123 4567 8902 05/2023 123 Any Declined
VISA 4111 1111 1111 1111 05/2023 123 Varying Depends on cent amount
AMEX 3456 7890 1234 564 05/2023 1234 Any Approved
AMEX 3714 4963 5398 431 05/2023 1234 Any Declined
AMEX 3787 3449 3671 000 05/2023 1234 Varying Depends on cent amount
JCB 3530 1113 3330 0000 05/2023 123 Any Approved
JCB 3566 0020 2036 0505 05/2023 123 Any Declined
JCB 3569 9900 0000 0009 05/2023 123 Varying Depends on cent amount


Fat Zebra will return errors to you in plain text format. When you receive your response from Fat Zebra you should check the response payload for the success value - this will be true or false depending on the outcome - please note, this only indicates if the request was accepted by Fat Zebra and then sent to your merchant bank, not if the transaction was approved or declined.

If the request is not successful you should check the errors value to see where the problem lies.

If the request is successful you should then check the response value and inspect the status value to determine whether or not the transaction was approved or declined.

Some of the errors you may receive include:

  • Invalid card number
  • Invalid expiry date (e.g. invalid format, or expiry date past)
  • Invalid amount
  • Invalid original transaction reference (in the case of refunds)