Top 5 Free Currency Converter APIs for Developers in 2025

In the fast-paced world of development, access to reliable and efficient tools can make a significant difference. When it comes to building applications that involve currency conversions, selecting the right currency converter API is crucial. Whether you're developing financial apps, e-commerce platforms, or travel booking systems, integrating an API that delivers accurate and real-time currency exchange rates API data is essential. To help you in your journey, we’ve compiled a list of the top five free currency converter APIs for developers in 2025.
ExchangeRate API
ExchangeRate API has earned its spot as one of the most trusted APIs for currency conversion. Offering real-time and historical currency exchange rates API data for over 150 currencies, it’s an excellent tool for developers looking to implement reliable conversion features. The free plan provides up to 1,500 API calls per month, which is sufficient for small-scale applications.
With easy integration, comprehensive documentation, and fast response times, this API is particularly appealing for developers working on budget-friendly projects. Its robust support for multiple programming languages makes it versatile and accessible to developers across different platforms.
Open Exchange Rates
Open Exchange Rates is another popular free currency converter API known for its simplicity and accuracy. The free plan includes hourly updates and support for over 170 currencies, making it a strong contender for apps that don’t require real-time data.
The API is lightweight and developer-friendly, with clear documentation that ensures seamless integration. For developers looking to scale, the premium plans offer advanced features such as live updates and additional data points. Its ease of use makes it a favorite among freelance developers and startups.
CurrencyLayer
If you’re searching for a currency exchange rates API with a focus on security and reliability, CurrencyLayer is worth considering. It provides accurate exchange rate data refreshed every hour for over 160 currencies. The free plan allows up to 250 API requests per month, making it suitable for small projects or testing environments.
CurrencyLayer offers a JSON-based API response, ensuring fast and lightweight data delivery. The platform also supports HTTPS for secure data transmission, which is critical for developers working on fintech applications. Its modular architecture makes it ideal for applications requiring tailored solutions.
XE Currency API
XE Currency API is a trusted name in the financial world and a go-to solution for developers who prioritize accuracy. Although its free tier is limited compared to others on this list, XE provides reliable exchange rate data for major currencies.
Its API includes features like historical data, real-time updates, and multi-language support. This makes it an excellent choice for developers working on global applications. The comprehensive documentation and dedicated developer support add significant value, ensuring a smooth implementation process.
Fixer.io
Fixer.io is a powerful and developer-friendly free currency converter API that offers real-time exchange rate data for over 170 currencies. The free tier includes daily updates and 1,000 API calls per month, making it a viable option for developers building non-enterprise applications.
What sets Fixer.io apart is its open-source nature and flexibility. It’s particularly popular among developers who value community-driven tools. With clear documentation and a simple setup process, Fixer.io is a must-try for developers looking to experiment with currency conversion features without incurring costs.
Choosing the Right API for Your Needs
When selecting a currency converter API, it’s important to evaluate your project’s specific requirements. Key factors to consider include:
API Call Limits: Ensure the free plan provides enough requests for your application’s needs.
Update Frequency: Choose an API that aligns with the real-time or periodic update requirements of your app.
Integration Ease: Opt for APIs with clear documentation and robust SDK support.
Security: Ensure the API supports HTTPS to protect sensitive data.
Conclusion
The right free currency exchange rates API can empower developers to create feature-rich applications without exceeding their budget. From the robust capabilities of ExchangeRate-API to the community-driven nature of Fixer.io, there’s no shortage of options for developers in 2025. By understanding your project’s needs and exploring the features of these APIs, you can seamlessly integrate currency conversion functionality into your applications.