# Testing
source: https://developer.mastercard.com/mastercard-benefits-and-experiences-portal/documentation/testing/index.md

## Test Data {#test-data}

### Test Partner ID {#test-partner-id}

When submitting requests in the Sandbox Environment, use `partnerId = 659` to get mock responses to your requests. Based on the payload of those responses, you will be able to test the behavior of your app before switching to the production environment.
Note: For a list of available environments, see [API Basics -\> Environments](https://developer.mastercard.com/mastercard-benefits-and-experiences-portal/documentation/api-basics/index.md#environments).

### Test Credit Card Data {#test-credit-card-data}

You can use any test credit card numbers for the `creditCardNumber` parameter in calls to the API endpoints within the Sandbox Environment using the test partner ID.

If you need a certain card number range to trigger a specific behavior, you will have to make arrangements with the API integration specialist who might be able to provide you with that test range.

When you switch over to the Production Environment, you will have to use real credit card numbers.

### Test Segment Codes {#test-segment-codes}

You can use any valid combination of letters and numbers for a segment code when using the test partner ID. When in Sandbox Environment, any segment will return a payload with selectable benefits.