The best was to test your integration is to signup for a sandbox account at https://stage-app.due.com and utilize our API Docs which can be found at https://api-docs.due.com. You can find a quick example on our developers' page at https://due.com/developers.
Our API Docs can be used to easily test the following:
- Charging a card or a customer
- Viewing Payments
- Setting webhooks for Payments
- Processing Refunds
- Managing Customer Data
Need more examples?
Contact support at https://support.due.com/ about specific examples you would like to see!