Dev Tutorial: Build a Currency Converter in React Using useState and useMemo

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A developer tutorial on DEV Community walks readers through building a simple currency converter application using React. The project converts USD to EUR, GBP, and JPY using fixed exchange rates, avoiding the complexity of a live API. It demonstrates how the useState hook manages user input and component state, while useMemo optimizes performance by memoizing calculated values and recomputing only when dependencies change. The interface includes a number input, two currency dropdowns, and a display for the converted result. The tutorial is aimed at React beginners looking to learn core concepts through a small, practical project.

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ProgrammingDEV Community ·

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