Currencylayer

Overview

Currencylayer is an API service that provides access to real-time and historical foreign exchange rate data. Launched in 2012, it offers a suite of endpoints designed to deliver current and past exchange rates for over 168 world currencies, including major fiat currencies and some cryptocurrencies. The API is structured as a RESTful service, returning data in JSON format, which simplifies integration into various applications.

Developers primarily use Currencylayer for applications requiring accurate and up-to-date currency information. This includes financial platforms displaying live market data, e-commerce sites needing to convert prices for international customers, and analytical tools performing historical trend analysis. The API aggregates exchange rate data from multiple commercial sources, aiming to provide reliable and consistent information. Its developer experience is characterized by clear documentation and code examples across several programming languages, including cURL for direct HTTP requests, PHP, Python, Node.js, Go, Ruby, and Java.

The service offers various core products, each addressing specific currency data needs. The Live Rates API provides instant exchange rates, useful for real-time dashboards or transactional systems. The Historical Rates API allows retrieval of past exchange rates for specific dates, essential for auditing, back-testing, or reporting. For more complex data needs, the Time-Series Data API enables fetching exchange rate fluctuations over a specified period, and the Change Tracking API monitors percentage changes between two dates. A dedicated Currency Conversion API simplifies direct currency-to-currency conversions without requiring manual rate lookups. Currencylayer is owned by apilayer GmbH, which is part of Idera, Inc., a company that also owns other API services like Fixer.

The API's ease of use, coupled with its comprehensive currency coverage and various data endpoints, positions it as a tool for developers needing to integrate currency exchange functionality into their products. Its compliance with GDPR standards addresses data privacy concerns for European users. The service is suitable for both small-scale projects using its free tier and large enterprise applications requiring high request volumes, with dedicated support and infrastructure for higher-tier plans.

Key features

• Live Rates API: Provides real-time exchange rates for over 168 world currencies, updated at frequent intervals.
• Historical Rates API: Allows retrieval of exchange rates for any specific date since 1999, useful for historical analysis and reporting.
• Currency Conversion API: Facilitates direct conversion between any two supported currencies, simplifying international transactions.
• Time-Series Data API: Delivers currency exchange rate data over a specified period, enabling trend analysis and charting.
• Change Tracking API: Monitors and reports percentage changes in exchange rates between two designated dates.
• JSON Format Responses: All API responses are delivered in JSON, making data parsing and integration straightforward for web and mobile applications.
• API Key Authentication: Secures API access using a unique API key appended to requests, as detailed in the Currencylayer authentication guide.
• Comprehensive Currency Coverage: Supports 168+ world currencies, including major fiat currencies and some digital currencies.
• Scalable Infrastructure: Designed to handle varying request volumes, from individual developers to large enterprise clients.
• GDPR Compliance: Adheres to General Data Protection Regulation standards for data handling and privacy.

Pricing

Currencylayer offers a tiered pricing model, including a free plan and several paid subscriptions to accommodate different usage levels. Pricing is subject to change; for the most current details, refer to the official Currencylayer product page.

The free plan is suitable for initial testing and small projects, providing access to live exchange rates. As usage scales or more advanced features like historical data, time-series, or currency conversion are required, users can upgrade to the Basic or Professional plans. Enterprise Plus plans are available for high-volume users requiring custom solutions and dedicated support.

Common integrations

Currencylayer's API is designed for integration into various software environments that require currency data. Due to its RESTful nature and JSON output, it can be consumed by nearly any programming language or platform.

• E-commerce Platforms: Integrate with online stores to display product prices in local currencies for international customers, using the Currency Conversion API endpoint.
• Financial Dashboards: Power real-time financial applications that track global currency movements, leveraging the Live Rates API for instant updates.
• Investment Analysis Tools: Incorporate historical exchange rate data for back-testing investment strategies or analyzing market trends over time with the Historical Rates API.
• Reporting and Analytics: Utilize time-series data to generate reports on currency fluctuations for business intelligence or regulatory compliance.
• Forex Trading Applications: Provide current and historical data feeds for foreign exchange trading platforms, though specific trading execution is outside the API's scope.
• Enterprise Resource Planning (ERP) Systems: Integrate for automated currency conversions in international invoicing, payroll, or accounting modules.

Alternatives

For developers evaluating currency exchange rate APIs, several alternatives to Currencylayer are available, each with distinct features and pricing models:

• Open Exchange Rates: Offers a free plan and paid tiers for real-time and historical exchange rates, with a focus on ease of use and broad currency coverage.
• ExchangeRate-API: Provides simple JSON API for current and historical exchange rates, including a free tier for up to 1,500 requests per month.
• Fixer: Also owned by apilayer GmbH, Fixer provides similar functionality to Currencylayer, focusing on real-time and historical foreign exchange rates with a simple REST API.

Getting started

To begin using the Currencylayer API, developers typically sign up for an API key and then make HTTP GET requests to the various endpoints. The following example demonstrates how to fetch live exchange rates using cURL, a common command-line tool for making HTTP requests. This example requests all available live exchange rates, with the base currency set to USD, and requires replacing YOUR_ACCESS_KEY with a valid API key obtained from the Currencylayer dashboard.

curl "http://api.currencylayer.com/live?access_key=YOUR_ACCESS_KEY&format=1"

The API response will be a JSON object containing the requested currency data. For example, a successful response for live rates might look like this:

{
  "success": true,
  "timestamp": 1678886400, // Example timestamp
  "source": "USD",
  "quotes": {
    "USDEUR": 0.925,
    "USDGBP": 0.812,
    "USDJPY": 130.56,
    "USDCAD": 1.350
  }
}

For retrieving historical data, the request would include a specific date. For instance, to get rates for March 15, 2023:

curl "http://api.currencylayer.com/historical?access_key=YOUR_ACCESS_KEY&date=2023-03-15&format=1"

Further examples and detailed explanations for various endpoints and programming languages are provided in the Currencylayer API documentation, which helps developers integrate the service into their specific application environments. HTTP status codes are used to indicate success or error conditions, allowing applications to handle responses programmatically.