Introduction to the Currency Converter App in React

Welcome to the first module of the Currency Converter App walkthrough. In this documentation series, we’ll build a fully functional currency converter using React and Vite. This app lets users choose two currencies, enter an amount, and instantly convert it using real-time exchange rates from a free API.

By the end of this project, you’ll not only have a working currency converter ready to deploy but also a strong foundation in handling APIs, state management, and reusable components in React.

This is a perfect beginner project because it’s practical, interactive, and demonstrates how real-world apps fetch and display live data. Let’s begin!

ReactJS is a popular JavaScript library developed by Meta (Facebook) that makes it simple to build interactive web applications. Instead of writing everything in plain JavaScript, React allows us to split the UI into small, reusable components.

In our Currency Converter App, we’ll use React features like:

• Component-Based Architecture: We’ll break the UI into components such as App, CurrencyConverter, and CurrencyDropdown.
• JSX Syntax: We’ll write HTML-like code directly inside JavaScript, which React transforms into real DOM elements.
• State Management with useState: We’ll manage user input, selected currencies, and converted values.
• Side Effects with useEffect: We’ll fetch live exchange rates whenever the user changes a currency or amount.

React is perfect for this app because exchange rates and conversions change dynamically based on user interaction and API data.

A currency converter app allows users to:

1. Select a base currency (e.g., USD).
2. Select a target currency (e.g., INR).
3. Enter an amount (e.g., 10 USD).
4. Instantly see the converted amount (e.g., 830 INR).

Our version of the app will include:

• A dropdown to pick “From” and “To” currencies.
• A real-time API call to fetch exchange rates.
• Instant calculations when the amount or currency is changed.
• A clean, responsive UI styled with TailwindCSS.

This makes the app both useful and educational, since you’ll learn how to:

• Fetch and handle data from an external API.
• Update the UI in real time as inputs change.
• Manage multiple states (amount, fromCurrency, toCurrency, result).
• Build reusable and scalable components.

By following this project, you’ll learn how to:

• Set up a React + Vite project.
• Break down the UI into logical React components.
• Work with APIs using fetch inside useEffect.
• Handle user inputs (dropdowns & number fields).
• Perform calculations dynamically and render results.
• Style using TailwindCSS for responsive design.

Deploy your project to Netlify (or similar hosting).