C9PG: Smarter Payments since 1995

Enterprise Level Payment Processing Gateway

C9 Payment API Integration​

From Developers to Developers… We Make It Easy

Table of Contents


Cloud9 Payment Gateway (C9PG) API is based on over 25 years of credit card processing middleware experience.  It is simple, consistent, and secure.

It is simple.

  • It is based on HTTPS and JSON, which are widely used in modern mainstream programs.
  • Developers can use PostMan, CURL, or our API website to try it out in minutes.
  • Developers can integrate with our API in a few days.

It is consistent.

  • It has the same format whether to connect to the cloud payment gateway, local payment terminals, or mobile payment devices.
  • Developers can write the integration once and immediately access all options by simply change the URL of the API.

It is secure.

  • It is channel encrypted using the industry standard.
  • The sensitive info in the API can be additionally encrypted.
  • Tokens can be utilized to prevent hacking.
  • The POS and the payment device can be on separate networks for the most secure PCI audit.

If you are familiar with JSON, we recommend that you jump directly to our JSON Swagger style OpenAPI sandbox.

Otherwise, please choose from a list below. Don’t see what you are looking for? Contact us and we will help you out.

Integration Platforms


HTML Javascript (Web Page Integration)




Developer Guide

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