Direct offers many resources to allow you extensive testing by payment method, integration mode or desired transaction result:

• Use the API explorer to send requests to any of our endpoints in our test environment. It works with both your PSPID/authentication credentials and even without them, enabling you to start testing right away!
• Create and customise requests with our Request Builder reflecting your business logic in your preferred programming language. It is a very useful tool especially in combination with our SDKs
• Our Test cases page contains card numbers and precise instructions to trigger specific scenarios (i.e. successful/declined transactions). The “Testing” tab in our dedicated payment method documentations contain payment method-specific information to tailor your requests