Developer Builds Flask Coupon Calculator to Solve Real Cashier Math Challenges

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A developer and cashier created a lightweight Flask web app called Coupon Calculator to simplify discount calculations at checkout. The project was motivated by the creator's personal struggle with dyscalculia, which makes mental math difficult during busy retail shifts. The app allows users to enter an original price and apply either a percentage or fixed discount, then instantly view the savings and final price. It includes input validation, protection against negative values, and currency-safe rounding to two decimal places. The tool was built as a practical, everyday solution and is available as a live web app.

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