What Is a Currency API? The Ultimate Guide for Developers
Published on May 19, 2025 by CurrencyDataFeed Team
A Currency API allows developers and businesses to fetch real-time and historical exchange rate data using HTTP requests. Whether you're running a financial dashboard, mobile app, or travel platform, integrating a forex API can automate conversions and provide timely market insights.
How Does It Work?
Currency APIs typically use REST endpoints or WebSockets. You send a request for specific currency pairs — such as USD to EUR — and receive structured JSON responses including bid/ask prices, last traded price, and timestamps. WebSockets offer real-time push updates, perfect for trading platforms and live feeds.
Key Use Cases
- Currency converters on websites and mobile apps
- Automated invoicing and billing in local currencies
- Multi-currency e-commerce checkout systems
- Financial charting, alerts, and technical analysis
Choosing the Right API
Here’s what to consider when selecting a currency API:
- Update Frequency: Sub-second latency is critical for trading apps
- Data Types: Forex, crypto, metals, historical OHLC, and technicals
- Scalability: Support for thousands of requests per second
- Reliability: Uptime guarantees and CDN-accelerated delivery
At CurrencyDataFeed.com, our API supports 180+ currencies and over 10,000 crypto pairs. We offer REST and WebSocket access, historical OHLC data, technical indicators like RSI/MACD, and much more.
Frequently Asked Questions
What is a currency API?
An API that returns real-time exchange rates via REST/HTTP or WebSocket.
Is it free?
CurrencyDataFeed offers a demo free plan — with upgrade options for higher usage or advanced data.
How accurate is the data?
We use aggregated and exchange-sourced data with up-to-the-second updates.