The Profit Margin Calculator app is a simple and user-friendly tool designed to help small business owners and entrepreneurs determine the most profitable selling price for their products. The app allows users to input their costs of goods sold, shipping cost, PayPal fees, and desired profit margin, and then calculates the optimal selling price for their products. The app is made by using OpenAI's GPT-3 model, which is also known as ChatGPT, it is a state-of-the-art language model that can generate human-like text. The app is easy to use, and the results are displayed in a clear and concise manner, making it an essential tool for anyone in business. The app is perfect for small business owners, entrepreneurs, and anyone who wants to make the most of their sales.