@exchangerateapi/sdk

The fastest way to access real-time mid-market exchange rates in JavaScript/TypeScript

Official JavaScript/TypeScript SDK for Exchange Rate API. Access real-time and historical mid-market exchange rates for 160+ currencies. Zero dependencies.

Why Choose This SDK?

• Zero Dependencies -- Uses only the built-in fetch API. Nothing to audit, nothing to break.
• TypeScript-First -- Full type definitions and IDE autocomplete out of the box.
• ESM + CommonJS -- Works everywhere: Node.js, Bun, Deno, and bundlers. Ships both ESM and CJS builds.
• Real-Time Data -- Rates updated every 60 seconds from Reuters (Refinitiv) and interbank feeds.
• Mid-Market Rates -- The true interbank rate -- no hidden spread or markup.
• 160+ Currencies -- Major, minor, and exotic currency pairs.

Installation

npm install @exchangerateapi/sdk

Quick Start

import { ExchangeRateAPI } from '@exchangerateapi/sdk';

const client = new ExchangeRateAPI({ apiKey: 'era_live_...' });

// Get latest rates
const { rates } = await client.latest({ base: 'USD', symbols: ['EUR', 'GBP', 'JPY'] });
console.log(rates); // { EUR: 0.92, GBP: 0.78, JPY: 149.5 }

// Convert currencies
const result = await client.convert('USD', 'EUR', 1000);
console.log(`$1,000 = EUR ${result.result}`);

Authentication

All API requests require a Bearer token. Get your free API key at exchange-rateapi.com/register.

const client = new ExchangeRateAPI({ apiKey: 'era_live_your_key_here' });

The SDK sends the key as a Bearer token in the Authorization header automatically.

You can also override the API key on a per-request basis:

const data = await client.latest({ apiKey: 'era_live_other_key' });

Configuration

const client = new ExchangeRateAPI({
  apiKey: 'era_live_...',       // Required. Your API key.
  baseUrl: 'https://exchange-rateapi.com', // Optional. Default shown.
  timeout: 10000,               // Optional. Request timeout in ms. Default: 10000.
});

API Methods

latest(options?)

Get the latest exchange rates.

// All rates from USD
const data = await client.latest();

// Specific symbols with EUR base
const data = await client.latest({ base: 'EUR', symbols: ['USD', 'GBP', 'JPY'] });

console.log(data.base);  // 'EUR'
console.log(data.date);  // '2026-05-10T12:00:00Z'
console.log(data.rates); // { USD: 1.08, GBP: 0.85, JPY: 162.3 }

forDate(date, options?)

Get exchange rates for a specific historical date.

// Using a string
const data = await client.forDate('2026-01-15');

// Using a Date object
const data = await client.forDate(new Date('2026-01-15'));

// With options
const data = await client.forDate('2026-01-15', {
  base: 'EUR',
  symbols: ['USD', 'GBP'],
});

timeSeries(startDate, endDate, options?)

Get exchange rate time series between two dates.

const data = await client.timeSeries('2026-01-01', '2026-03-31', {
  base: 'USD',
  symbols: ['EUR', 'GBP'],
});

// Access rates by date
console.log(data.rates['2026-01-15']); // { EUR: 0.92, GBP: 0.78 }

convert(from, to, amount, options?)

Convert an amount between two currencies.

// Current rate
const result = await client.convert('USD', 'EUR', 1000);
console.log(`$1,000 = EUR ${result.result}`);

// Historical conversion
const result = await client.convert('USD', 'EUR', 1000, {
  date: '2026-01-15',
});
console.log(`Rate on Jan 15: ${result.rate}`);

getRate(from, to, amount?)

Get exchange rate between two currencies.

const rate = await client.getRate('USD', 'EUR');
console.log(`1 USD = ${rate.rate} EUR`);

// With amount
const rate = await client.getRate('USD', 'EUR', 1000);
console.log(`$1,000 = EUR ${rate.to.amount}`);

getRates(source, target)

Get authenticated exchange rates with metadata.

const rates = await client.getRates('USD', 'EUR');
rates.forEach(r => console.log(`${r.source}/${r.target}: ${r.rate} at ${r.time}`));

getHistoricalRates(source, target, period?)

Get historical rates by period. Supported periods: 1d, 7d, 30d, 1y.

const history = await client.getHistoricalRates('USD', 'EUR', '30d');
history.rates.forEach(point => {
  console.log(`${point.time}: ${point.rate}`);
});

symbols()

Get all supported currency symbols.

const { symbols } = await client.symbols();
console.log(symbols);
// { USD: 'United States Dollar', EUR: 'Euro', GBP: 'British Pound', ... }

// Build a currency dropdown
const options = Object.entries(symbols).map(([code, name]) => ({ code, name }));

Error Handling

import { ExchangeRateAPI, ExchangeRateAPIError } from '@exchangerateapi/sdk';

const client = new ExchangeRateAPI({ apiKey: 'era_live_...' });

try {
  const data = await client.latest();
} catch (err) {
  if (err instanceof ExchangeRateAPIError) {
    console.error(`API error: ${err.message} (status: ${err.status})`);
  }
}

CommonJS Usage

const { ExchangeRateAPI } = require('@exchangerateapi/sdk');

const client = new ExchangeRateAPI({ apiKey: 'era_live_...' });

Links

• API Documentation
• Register (Free)
• Dashboard
• Status
• GitHub

License

MIT - see LICENSE for details.