If you're looking for a Simple DC-DC Power free Design tool, check this out.

I wanted to share a cool tool we discovered when enaging with Maxim Integrated last year. If you're new to DC-DC power design and are looking for a tool to speed up your design, you should check out EE-Sim

How to Design a Power Supply in Five Minutes or Less with the EE-Sim Online Design Tool

https://www.rs-online.com/designspark/how-to-design-a-power-supply-in-five-minutes-or-less-with-the-maxim-ee-sim-online-design-tool