Open banking is a regulatory framework allowing customers to share their banking data with third-party service providers securely. This concept has gained traction recently, with many countries implementing it to increase competition and innovation in the financial industry. This article will examine how open banking is being implemented in Indonesia, Singapore, and Australia through triangular insight, mainly examining API (Application Programming Interface) standardization, security issues, a regulatory sandbox, customer insights, and user experiences. This article, using normative legal research, demonstrates that open banking is a regulatory framework that is indeed gaining traction in many countries, including Indonesia, Singapore, and Australia. While some challenges and weaknesses are associated with implementing open banking, it can potentially increase competition, innovation, and consumer welfare in the financial industry. Legal research and insights gleaned through triangular insight have been instrumental in developing the legal frameworks for open banking and ensuring that it is implemented securely, transparently, and ethically.