This paper presents an industry first HTML5 based WEBENCH® Power Designer for designing switch-mode power supplies in a few minutes. The presented tool is specifically designed by focusing on often ignored User Interface (UI) as well as User Experience (UX) aspects of design tools with the latest HTML5 technologies such as Angular 5. The paper intuitively discusses the basics of power supply design and illustrates how the HTML5 Power designer can be used to quickly select, customize, simulate and export an optimized design to popular CAD tools. By using this tool, users get a customized power supply design in a couple of seconds which reduces overall design cycle time and enables them to bring products to market faster. This is a good starting point for students to learn power supply design and quickly prototype a power supply whereas for professionals it is an advanced tool which can provide highly customized and optimized power supply.