How to Convert Currencies in Real-Time with a Free API

How to Convert Currencies in Real-Time with a Free API If your application handles international transactions, displays prices in multiple currencies, or generates financial reports across regions, you need reliable exchange rate data. Most currency APIs either charge immediately, require credit card signup for a "free" tier, or throttle aggressively after a handful of requests. This article shows how to convert currencies, fetch historical rates, and list supported currencies using a free API backed by European Central Bank data, with working JavaScript examples you can drop into your project today. Where the rates come from The European Central Bank publishes reference exchange rates daily for 30+ currencies against the EUR. These are the same rates used by financial institutions across Europe for settlement and accounting. The data goes back to January 1999, which means you can query historical rates for any business day in the last 27 years. The API wraps the Frankfurter API , whic