How to Build a Real-Time Currency Converter with JavaScript: Step-by-Step Tutorial

• 12 min read

Building a currency converter is one of the most practical JavaScript projects for web developers. Whether you're creating a travel app, e-commerce platform, or financial dashboard, understanding how to fetch real-time exchange rates and convert currencies is essential. This tutorial walks you through creating a production-ready currency converter from scratch.

Currency converters are everywhere on the web, but many developers struggle to implement them correctly. The challenges include choosing the right exchange rate API, handling decimal precision, formatting numbers according to locale standards, and creating a smooth user experience.

In this tutorial, you'll learn how to build a currency converter that fetches real-time exchange rates, performs accurate conversions, and displays results in properly formatted currency notation. We'll use vanilla JavaScript to keep things simple and portable, though the concepts apply to any framework.

1. Prerequisites and Setup

What You'll Need

Before we begin, make sure you have:

  • Basic knowledge of HTML, CSS, and JavaScript
  • Understanding of async/await and Promises in JavaScript
  • A text editor or IDE (VS Code, Sublime Text, etc.)
  • A modern web browser with developer tools
  • An API key from an exchange rate provider (we'll cover this)

Choosing an Exchange Rate API

For this tutorial, we'll use a free exchange rate API. The best free APIs provide:

  • Daily updated exchange rates from reliable sources
  • Support for 150+ currencies
  • Simple REST API with JSON responses
  • Reasonable rate limits (1000+ requests per month)
  • No credit card required for signup

Pro Tip: For production applications, always sign up for an API key even if the service offers free access. This gives you higher rate limits, better support, and protects your app from IP-based throttling.

2. Building the HTML Structure

Let's start with a clean, semantic HTML structure. We'll create a form with two currency selectors and amount inputs: 

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Currency Converter - Real-Time Exchange Rates</title>
    <link rel="stylesheet" href="styles.css">
</head>
<body>
    <div class="container">
        <header>
            <h1>Currency Converter</h1>
            <p class="subtitle">Real-time exchange rates</p>
        </header>

        <div class="converter-card">
            <!-- Amount Input -->
            <div class="input-group">
                <label for="amount">Amount</label>
                <input
                    type="number"
                    id="amount"
                    value="100"
                    min="0"
                    step="0.01"
                    placeholder="Enter amount"
                >
            </div>

            <!-- From Currency -->
            <div class="input-group">
                <label for="fromCurrency">From</label>
                <select id="fromCurrency" class="currency-select">
                    <option value="USD" selected>USD - US Dollar</option>
                    <!-- Will be populated by JavaScript -->
                </select>
            </div>

            <!-- Swap Button -->
            <button class="swap-button" id="swapBtn" aria-label="Swap currencies">
                ⇅
            </button>

            <!-- To Currency -->
            <div class="input-group">
                <label for="toCurrency">To</label>
                <select id="toCurrency" class="currency-select">
                    <option value="EUR">EUR - Euro</option>
                    <!-- Will be populated by JavaScript -->
                </select>
            </div>

            <!-- Result Display -->
            <div class="result-box" id="result">
                <div class="loading" style="display: none;">Converting...</div>
                <div class="result-amount">--</div>
                <div class="exchange-rate"></div>
            </div>

            <!-- Convert Button -->
            <button class="convert-button" id="convertBtn">Convert</button>

            <!-- Error Message -->
            <div class="error-message" id="errorMsg" style="display: none;"></div>

            <!-- Last Updated -->
            <div class="last-updated" id="lastUpdated"></div>
        </div>
    </div>

    <script src="app.js"></script>
</body>
</html>

This structure includes all the essential elements:

  • Amount input with decimal support (step="0.01")
  • Dropdown selectors for source and target currencies
  • A swap button to quickly reverse the conversion direction
  • Result display area with loading state
  • Error message container for user feedback
  • Last updated timestamp for rate transparency

3. Styling with CSS

Let's add clean, modern styling that works on all devices: 

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    max-width: 600px;
    width: 100%;
}

header {
    text-align: center;
    color: white;
    margin-bottom: 30px;
}

header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.1rem;
    opacity: 0.9;
}

.converter-card {
    background: white;
    border-radius: 16px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

.input-group {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 8px;
    color: #374151;
    font-weight: 600;
    font-size: 0.9rem;
}

input[type="number"],
.currency-select {
    width: 100%;
    padding: 14px;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s;
}

input[type="number"]:focus,
.currency-select:focus {
    outline: none;
    border-color: #667eea;
}

.swap-button {
    width: 100%;
    padding: 12px;
    background: #f3f4f6;
    border: none;
    border-radius: 8px;
    font-size: 24px;
    cursor: pointer;
    transition: background 0.3s;
    margin-bottom: 20px;
}

.swap-button:hover {
    background: #e5e7eb;
}

.convert-button {
    width: 100%;
    padding: 16px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 18px;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s;
}

.convert-button:hover {
    transform: translateY(-2px);
}

.result-box {
    background: #f9fafb;
    padding: 30px;
    border-radius: 12px;
    margin: 20px 0;
    text-align: center;
}

.result-amount {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 10px;
}

.exchange-rate {
    color: #6b7280;
    font-size: 0.9rem;
}

.loading {
    color: #667eea;
    font-weight: 600;
}

.error-message {
    background: #fee2e2;
    color: #991b1b;
    padding: 12px;
    border-radius: 8px;
    margin-top: 15px;
    font-size: 0.9rem;
}

.last-updated {
    text-align: center;
    color: #9ca3af;
    font-size: 0.8rem;
    margin-top: 15px;
}

@media (max-width: 640px) {
    .converter-card {
        padding: 24px;
    }

    header h1 {
        font-size: 2rem;
    }
}

4. Fetching Exchange Rates from API

Setting Up API Configuration

Create the JavaScript file (app.js) and start with the API configuration: 

// API Configuration
const API_KEY = 'your_api_key_here'; // Replace with your actual API key
const API_BASE_URL = 'https://api.unirateapi.com/v1';

// Cache for exchange rates
let ratesCache = null;
let cacheTimestamp = null;
const CACHE_DURATION = 3600000; // 1 hour in milliseconds

// Popular currencies for the dropdown
const POPULAR_CURRENCIES = [
    { code: 'USD', name: 'US Dollar' },
    { code: 'EUR', name: 'Euro' },
    { code: 'GBP', name: 'British Pound' },
    { code: 'JPY', name: 'Japanese Yen' },
    { code: 'AUD', name: 'Australian Dollar' },
    { code: 'CAD', name: 'Canadian Dollar' },
    { code: 'CHF', name: 'Swiss Franc' },
    { code: 'CNY', name: 'Chinese Yuan' },
    { code: 'INR', name: 'Indian Rupee' },
    { code: 'MXN', name: 'Mexican Peso' },
    { code: 'BRL', name: 'Brazilian Real' },
    { code: 'ZAR', name: 'South African Rand' }
];

Fetching Exchange Rates

Implement the function to fetch rates with caching for better performance: 

/**
 * Fetch exchange rates from API with caching
 * @param {string} baseCurrency - Base currency code (e.g., 'USD')
 * @returns {Promise<Object>} - Rates object
 */
async function fetchExchangeRates(baseCurrency = 'USD') {
    // Check cache validity
    const now = Date.now();
    if (ratesCache && cacheTimestamp && (now - cacheTimestamp) < CACHE_DURATION) {
        console.log('Using cached rates');
        return ratesCache;
    }

    try {
        const response = await fetch(
            `${API_BASE_URL}/latest/${baseCurrency}?api_key=${API_KEY}`
        );

        if (!response.ok) {
            throw new Error(`HTTP error! status: ${response.status}`);
        }

        const data = await response.json();

        // Cache the results
        ratesCache = data.rates;
        cacheTimestamp = now;

        return data.rates;

    } catch (error) {
        console.error('Error fetching exchange rates:', error);
        throw new Error('Failed to fetch exchange rates. Please try again.');
    }
}

/**
 * Get specific exchange rate between two currencies
 * @param {string} from - Source currency
 * @param {string} to - Target currency
 * @returns {Promise<number>} - Exchange rate
 */
async function getExchangeRate(from, to) {
    if (from === to) {
        return 1;
    }

    const rates = await fetchExchangeRates(from);

    if (!rates[to]) {
        throw new Error(`Exchange rate not available for ${to}`);
    }

    return rates[to];
}

Security Warning: In production, never expose your API key in client-side JavaScript. Instead, create a backend endpoint that proxies requests to the exchange rate API, keeping your key secure on the server.

5. Implementing Conversion Logic

Core Conversion Function

Now let's implement the conversion logic with proper rounding and error handling: 

/**
 * Convert amount from one currency to another
 * @param {number} amount - Amount to convert
 * @param {string} from - Source currency
 * @param {string} to - Target currency
 * @returns {Promise<Object>} - Conversion result
 */
async function convertCurrency(amount, from, to) {
    if (!amount || amount <= 0) {
        throw new Error('Please enter a valid amount');
    }

    if (!from || !to) {
        throw new Error('Please select both currencies');
    }

    try {
        const rate = await getExchangeRate(from, to);
        const convertedAmount = amount * rate;

        return {
            originalAmount: amount,
            convertedAmount: convertedAmount,
            fromCurrency: from,
            toCurrency: to,
            exchangeRate: rate,
            timestamp: new Date().toISOString()
        };

    } catch (error) {
        console.error('Conversion error:', error);
        throw error;
    }
}

/**
 * Initialize currency dropdowns
 */
function initializeCurrencyDropdowns() {
    const fromSelect = document.getElementById('fromCurrency');
    const toSelect = document.getElementById('toCurrency');

    POPULAR_CURRENCIES.forEach(currency => {
        // From currency dropdown
        const option1 = document.createElement('option');
        option1.value = currency.code;
        option1.textContent = `${currency.code} - ${currency.name}`;
        fromSelect.appendChild(option1);

        // To currency dropdown
        const option2 = document.createElement('option');
        option2.value = currency.code;
        option2.textContent = `${currency.code} - ${currency.name}`;
        toSelect.appendChild(option2);
    });

    // Set default values
    fromSelect.value = 'USD';
    toSelect.value = 'EUR';
}

UI Event Handlers

Connect the conversion logic to the user interface: 

/**
 * Handle conversion button click
 */
async function handleConvert() {
    const amount = parseFloat(document.getElementById('amount').value);
    const fromCurrency = document.getElementById('fromCurrency').value;
    const toCurrency = document.getElementById('toCurrency').value;

    const resultDiv = document.getElementById('result');
    const errorDiv = document.getElementById('errorMsg');
    const loadingDiv = resultDiv.querySelector('.loading');
    const resultAmountDiv = resultDiv.querySelector('.result-amount');
    const exchangeRateDiv = resultDiv.querySelector('.exchange-rate');

    // Clear previous error
    errorDiv.style.display = 'none';

    // Show loading state
    loadingDiv.style.display = 'block';
    resultAmountDiv.textContent = '--';
    exchangeRateDiv.textContent = '';

    try {
        const result = await convertCurrency(amount, fromCurrency, toCurrency);

        // Hide loading
        loadingDiv.style.display = 'none';

        // Display result with proper formatting
        resultAmountDiv.textContent = formatCurrency(
            result.convertedAmount,
            result.toCurrency
        );

        // Display exchange rate
        exchangeRateDiv.textContent =
            `1 ${fromCurrency} = ${result.exchangeRate.toFixed(4)} ${toCurrency}`;

        // Update last updated time
        updateLastUpdatedTime();

    } catch (error) {
        loadingDiv.style.display = 'none';
        errorDiv.textContent = error.message;
        errorDiv.style.display = 'block';
    }
}

/**
 * Handle swap button click
 */
function handleSwap() {
    const fromSelect = document.getElementById('fromCurrency');
    const toSelect = document.getElementById('toCurrency');

    // Swap values
    const temp = fromSelect.value;
    fromSelect.value = toSelect.value;
    toSelect.value = temp;

    // Trigger conversion if amount exists
    const amount = document.getElementById('amount').value;
    if (amount) {
        handleConvert();
    }
}

/**
 * Update last updated timestamp
 */
function updateLastUpdatedTime() {
    const lastUpdatedDiv = document.getElementById('lastUpdated');
    const now = new Date();
    lastUpdatedDiv.textContent = `Rates updated: ${now.toLocaleTimeString()}`;
}

6. Formatting Currency with Intl.NumberFormat

Proper Currency Formatting

Use the Intl.NumberFormat API for locale-aware currency formatting. This handles decimal places, thousands separators, and currency symbols correctly: 

/**
 * Format number as currency with proper locale formatting
 * @param {number} amount - Amount to format
 * @param {string} currency - Currency code
 * @param {string} locale - Locale (defaults to user's locale)
 * @returns {string} - Formatted currency string
 */
function formatCurrency(amount, currency, locale = 'en-US') {
    // Handle special currencies with different decimal places
    const minorUnits = getMinorUnits(currency);

    try {
        return new Intl.NumberFormat(locale, {
            style: 'currency',
            currency: currency,
            minimumFractionDigits: minorUnits,
            maximumFractionDigits: minorUnits
        }).format(amount);
    } catch (error) {
        // Fallback for unsupported currencies
        return `${currency} ${amount.toFixed(minorUnits)}`;
    }
}

/**
 * Get the number of decimal places (minor units) for a currency
 * Following ISO 4217 standards
 * @param {string} currency - Currency code
 * @returns {number} - Number of decimal places
 */
function getMinorUnits(currency) {
    // Currencies with zero decimal places
    const zeroDecimalCurrencies = [
        'JPY', 'KRW', 'VND', 'CLP', 'TWD', 'PYG', 'ISK'
    ];

    // Currencies with three decimal places
    const threeDecimalCurrencies = [
        'BHD', 'JOD', 'KWD', 'OMR', 'TND'
    ];

    if (zeroDecimalCurrencies.includes(currency)) {
        return 0;
    } else if (threeDecimalCurrencies.includes(currency)) {
        return 3;
    }

    // Most currencies use 2 decimal places
    return 2;
}

/**
 * Format large numbers with compact notation
 * @param {number} amount - Amount to format
 * @returns {string} - Formatted string (e.g., "1.2M", "3.4K")
 */
function formatCompactNumber(amount) {
    return new Intl.NumberFormat('en-US', {
        notation: 'compact',
        compactDisplay: 'short'
    }).format(amount);
}

Best Practice: Always use Intl.NumberFormat instead of manually formatting currencies. It handles international standards automatically, including right-to-left languages, different symbol positions, and various decimal separators.

7. Error Handling and Edge Cases

Input Validation

Robust error handling ensures your converter works reliably: 

/**
 * Validate user input
 * @param {string} amountStr - Amount as string
 * @returns {Object} - Validation result
 */
function validateInput(amountStr) {
    const errors = [];

    // Check if empty
    if (!amountStr || amountStr.trim() === '') {
        errors.push('Amount is required');
    }

    // Convert to number
    const amount = parseFloat(amountStr);

    // Check if valid number
    if (isNaN(amount)) {
        errors.push('Please enter a valid number');
    }

    // Check if positive
    if (amount <= 0) {
        errors.push('Amount must be greater than zero');
    }

    // Check if too large (prevent API issues)
    if (amount > 999999999999) {
        errors.push('Amount is too large');
    }

    return {
        valid: errors.length === 0,
        errors: errors,
        amount: amount
    };
}

/**
 * Handle API errors with user-friendly messages
 * @param {Error} error - The error object
 * @returns {string} - User-friendly error message
 */
function getErrorMessage(error) {
    if (error.message.includes('Failed to fetch')) {
        return 'Network error. Please check your internet connection.';
    }

    if (error.message.includes('429')) {
        return 'Rate limit exceeded. Please try again in a few minutes.';
    }

    if (error.message.includes('401') || error.message.includes('403')) {
        return 'API authentication error. Please check your API key.';
    }

    if (error.message.includes('404')) {
        return 'Currency not found. Please select a valid currency.';
    }

    // Return original message or generic error
    return error.message || 'An unexpected error occurred. Please try again.';
}

Offline Functionality

Add fallback rates for when the API is unavailable: 

// Fallback rates (updated daily in production)
const FALLBACK_RATES = {
    'USD': { 'EUR': 0.92, 'GBP': 0.79, 'JPY': 148.50, 'AUD': 1.52 },
    'EUR': { 'USD': 1.09, 'GBP': 0.86, 'JPY': 161.50, 'AUD': 1.65 },
    // Add more as needed
};

/**
 * Get exchange rate with fallback
 * @param {string} from - Source currency
 * @param {string} to - Target currency
 * @returns {Promise<number>} - Exchange rate
 */
async function getExchangeRateWithFallback(from, to) {
    try {
        return await getExchangeRate(from, to);
    } catch (error) {
        console.warn('Using fallback rates due to API error');

        // Try fallback rates
        if (FALLBACK_RATES[from] && FALLBACK_RATES[from][to]) {
            return FALLBACK_RATES[from][to];
        }

        // If no fallback available, throw error
        throw new Error('Exchange rate not available offline');
    }
}

8. Advanced Features and Enhancements

Auto-Convert on Input

Add real-time conversion as users type: 

// Debounce function to limit API calls
function debounce(func, wait) {
    let timeout;
    return function executedFunction(...args) {
        const later = () => {
            clearTimeout(timeout);
            func(...args);
        };
        clearTimeout(timeout);
        timeout = setTimeout(later, wait);
    };
}

// Auto-convert with debouncing
const autoConvert = debounce(handleConvert, 500);

// Add to initialization
function initializeApp() {
    initializeCurrencyDropdowns();

    // Event listeners
    document.getElementById('convertBtn').addEventListener('click', handleConvert);
    document.getElementById('swapBtn').addEventListener('click', handleSwap);

    // Auto-convert on input change
    document.getElementById('amount').addEventListener('input', autoConvert);
    document.getElementById('fromCurrency').addEventListener('change', handleConvert);
    document.getElementById('toCurrency').addEventListener('change', handleConvert);

    // Initial conversion
    handleConvert();
}

// Initialize when DOM is ready
document.addEventListener('DOMContentLoaded', initializeApp);

Currency Search Feature

Make it easier to find currencies with a search filter: 

/**
 * Filter currency dropdown based on search input
 * @param {string} searchTerm - Search query
 * @param {HTMLSelectElement} selectElement - Dropdown element
 */
function filterCurrencies(searchTerm, selectElement) {
    const options = selectElement.querySelectorAll('option');
    const term = searchTerm.toLowerCase();

    options.forEach(option => {
        const text = option.textContent.toLowerCase();
        option.style.display = text.includes(term) ? 'block' : 'none';
    });
}

Historical Charts

Add a chart showing exchange rate trends using Chart.js: 

/**
 * Fetch historical exchange rates
 * @param {string} from - Source currency
 * @param {string} to - Target currency
 * @param {number} days - Number of days of history
 * @returns {Promise<Array>} - Historical data
 */
async function fetchHistoricalRates(from, to, days = 30) {
    const endDate = new Date();
    const startDate = new Date();
    startDate.setDate(startDate.getDate() - days);

    const response = await fetch(
        `${API_BASE_URL}/timeseries?` +
        `start_date=${startDate.toISOString().split('T')[0]}&` +
        `end_date=${endDate.toISOString().split('T')[0]}&` +
        `base=${from}&` +
        `currencies=${to}&` +
        `api_key=${API_KEY}`
    );

    const data = await response.json();
    return data.rates;
}

Enhancement Ideas: Consider adding features like conversion history (using localStorage), favorite currency pairs, keyboard shortcuts for power users, and PWA support for offline use.

Complete Working Example

Here's the complete app.js file with all features integrated: 

// Complete Currency Converter Application
const API_KEY = 'your_api_key_here';
const API_BASE_URL = 'https://api.unirateapi.com/v1';

let ratesCache = null;
let cacheTimestamp = null;
const CACHE_DURATION = 3600000;

const POPULAR_CURRENCIES = [
    { code: 'USD', name: 'US Dollar' },
    { code: 'EUR', name: 'Euro' },
    { code: 'GBP', name: 'British Pound' },
    { code: 'JPY', name: 'Japanese Yen' },
    { code: 'AUD', name: 'Australian Dollar' },
    { code: 'CAD', name: 'Canadian Dollar' },
    { code: 'CHF', name: 'Swiss Franc' },
    { code: 'CNY', name: 'Chinese Yuan' }
];

async function fetchExchangeRates(baseCurrency = 'USD') {
    const now = Date.now();
    if (ratesCache && cacheTimestamp && (now - cacheTimestamp) < CACHE_DURATION) {
        return ratesCache;
    }

    const response = await fetch(
        `${API_BASE_URL}/latest/${baseCurrency}?api_key=${API_KEY}`
    );
    const data = await response.json();

    ratesCache = data.rates;
    cacheTimestamp = now;

    return data.rates;
}

async function convertCurrency(amount, from, to) {
    const rates = await fetchExchangeRates(from);
    const rate = rates[to];
    return {
        convertedAmount: amount * rate,
        exchangeRate: rate
    };
}

function formatCurrency(amount, currency) {
    const minorUnits = getMinorUnits(currency);
    return new Intl.NumberFormat('en-US', {
        style: 'currency',
        currency: currency,
        minimumFractionDigits: minorUnits,
        maximumFractionDigits: minorUnits
    }).format(amount);
}

function getMinorUnits(currency) {
    const zero = ['JPY', 'KRW', 'VND'];
    const three = ['BHD', 'JOD', 'KWD'];
    if (zero.includes(currency)) return 0;
    if (three.includes(currency)) return 3;
    return 2;
}

async function handleConvert() {
    const amount = parseFloat(document.getElementById('amount').value);
    const from = document.getElementById('fromCurrency').value;
    const to = document.getElementById('toCurrency').value;

    try {
        const result = await convertCurrency(amount, from, to);
        document.querySelector('.result-amount').textContent =
            formatCurrency(result.convertedAmount, to);
        document.querySelector('.exchange-rate').textContent =
            `1 ${from} = ${result.exchangeRate.toFixed(4)} ${to}`;
    } catch (error) {
        document.getElementById('errorMsg').textContent = error.message;
        document.getElementById('errorMsg').style.display = 'block';
    }
}

function initializeCurrencyDropdowns() {
    const fromSelect = document.getElementById('fromCurrency');
    const toSelect = document.getElementById('toCurrency');

    POPULAR_CURRENCIES.forEach(currency => {
        fromSelect.add(new Option(`${currency.code} - ${currency.name}`, currency.code));
        toSelect.add(new Option(`${currency.code} - ${currency.name}`, currency.code));
    });
}

document.addEventListener('DOMContentLoaded', () => {
    initializeCurrencyDropdowns();
    document.getElementById('convertBtn').addEventListener('click', handleConvert);
    document.getElementById('swapBtn').addEventListener('click', () => {
        const from = document.getElementById('fromCurrency');
        const to = document.getElementById('toCurrency');
        [from.value, to.value] = [to.value, from.value];
        handleConvert();
    });
    handleConvert();
});

Conclusion

You now have a fully functional, production-ready currency converter built with vanilla JavaScript. This implementation includes all the essential features: real-time exchange rate fetching, proper currency formatting, error handling, caching, and a polished user interface.

Key takeaways from this tutorial:

  • Always use Intl.NumberFormat for currency formatting to respect international standards
  • Implement caching to reduce API calls and improve performance
  • Handle different currency decimal places (minor units) according to ISO 4217
  • Provide clear error messages and fallback functionality
  • Never expose API keys in client-side code for production applications
  • Use async/await for clean, readable asynchronous code

From here, you can extend this converter with features like historical charts, conversion history, favorite currency pairs, or integrate it into a larger application. The core patterns demonstrated here scale well for any currency-related feature you might need to build.

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Learn how to integrate forex APIs in Python applications with complete examples using requests, pandas, and best practices for production systems.

Need a Reliable Exchange Rate API?

Building a currency converter requires accurate, up-to-date exchange rate data. Get real-time and historical rates for 170+ currencies, with 99.9% uptime and developer-friendly documentation. Perfect for fintech apps, e-commerce platforms, and financial tools.

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