Czech National Bank SDKs & Libraries: Official & Community (2026)

SDKs overview

The Czech National Bank (CNB) provides web services for accessing official exchange rates, primarily through direct XML and JSON endpoints rather than offering dedicated official Software Development Kits (SDKs) on its developer portal. This approach means developers typically interact with the API by making standard HTTP requests and parsing the returned data. The absence of official SDKs encourages the developer community to create and maintain libraries in various programming languages, which wrap these HTTP interactions and simplify data consumption.

These community-driven libraries often abstract away the complexities of fetching and parsing the XML or JSON responses, providing language-specific objects or methods for accessing exchange rate data. This includes functionalities such as retrieving current daily rates, historical rates for specific dates, and lists of available currencies. Developers can integrate these libraries into applications requiring up-to-date or past exchange rate information involving the Czech Koruna (CZK) and other major currencies.

The CNB's web services are designed for straightforward access, requiring no authentication or API keys, which further simplifies the integration process for both direct API consumers and users of community SDKs. This open access model reduces the barrier to entry for developers building financial applications, research tools, or other services that depend on official Czech exchange rate data.

Official SDKs by language

The Czech National Bank does not provide official SDKs for its exchange rate web services. Instead, it offers direct HTTP endpoints that return data in XML or JSON formats as described in its documentation. Developers are expected to consume these endpoints directly or use third-party libraries. This model aligns with a common approach for exposing public data, where the emphasis is on accessible data formats rather than pre-packaged client libraries.

For direct consumption, developers can use standard HTTP client libraries available in most programming languages. For example, in Python, requests can fetch data, and xml.etree.ElementTree or json modules can parse it. In JavaScript, fetch or XMLHttpRequest can retrieve the data, and built-in JSON parsers manage the response. This flexibility allows developers to choose tools and methods that best suit their existing technology stacks and project requirements.

While official SDKs offer benefits like consistent design and direct support, their absence from the CNB's offerings means developers rely on robust community contributions or custom implementations for their projects. For developers seeking to understand API interaction patterns, Mozilla's Fetch API guide provides a comprehensive overview of making HTTP requests in web environments.

Installation

Since there are no official SDKs, installation typically refers to integrating community-contributed libraries or setting up standard HTTP client libraries. The process varies by programming language and the specific community library chosen.

Python

For Python, developers often use requests for HTTP communication and xml.etree.ElementTree or json for parsing. A common installation method for requests is via pip:

pip install requests

Community libraries, if available, would also be installed via pip, for example:

pip install cnb-exchange-rates # Example of a hypothetical community library

JavaScript (Node.js/Browser)

In JavaScript environments, developers can use the built-in fetch API in browsers or Node.js (with a polyfill or native support). For Node.js, a popular HTTP client is axios:

npm install axios

Community libraries for Node.js would also be installed via npm:

npm install cnb-rates # Example of a hypothetical community library

PHP

PHP projects often use GuzzleHttp/guzzle for making HTTP requests, installed via Composer:

composer require guzzlehttp/guzzle

Community libraries would similarly be installed via Composer:

composer require cnb/exchange-rates-bundle # Example of a hypothetical community library

It is important to consult the specific documentation for any chosen community library for precise installation instructions and dependencies, as these can change over time.

Quickstart example

This quickstart demonstrates fetching the current daily exchange rates from the Czech National Bank's API using Python. The example retrieves the XML data, parses it, and prints the exchange rates.

Python Example (Current Daily Rates)

This Python snippet uses the requests library to fetch the daily exchange rate data and xml.etree.ElementTree to parse the XML response. This approach is typical when official SDKs are not provided.

import requests
import xml.etree.ElementTree as ET

def get_current_exchange_rates():
    url = "https://www.cnb.cz/cs/financni_trhy/devizovy_trh/kurzy_devizoveho_trhu/denni_kurz.xml"
    try:
        response = requests.get(url)
        response.raise_for_status() # Raise an exception for HTTP errors (4xx or 5xx)

        root = ET.fromstring(response.content)

        print("Daily Exchange Rates (Czech National Bank):")
        print("------------------------------------------")
        date = root.find('.//cnb:date', namespaces={'cnb': 'http://www.cnb.cz/cnb_export/cnb_export.xsd'}).text if root.find('.//cnb:date', namespaces={'cnb': 'http://www.cnb.cz/cnb_export/cnb_export.xsd'}) is not None else 'N/A'
        print(f"Date: {date}")

        for rate_element in root.findall('.//cnb:row', namespaces={'cnb': 'http://www.cnb.cz/cnb_export/cnb_export.xsd'}):
            country = rate_element.get('country')
            currency = rate_element.get('currency')
            amount = rate_element.get('amount')
            code = rate_element.get('code')
            rate = rate_element.get('rate')
            print(f"  {country} ({currency}, {amount} {code}): {rate} CZK")

    except requests.exceptions.HTTPError as http_err:
        print(f"HTTP error occurred: {http_err}")
    except requests.exceptions.ConnectionError as conn_err:
        print(f"Connection error occurred: {conn_err}")
    except requests.exceptions.Timeout as timeout_err:
        print(f"Timeout error occurred: {timeout_err}")
    except requests.exceptions.RequestException as req_err:
        print(f"An error occurred: {req_err}")
    except ET.ParseError as parse_err:
        print(f"XML parsing error: {parse_err}")

if __name__ == "__main__":
    get_current_exchange_rates()

This example demonstrates:

• Making an HTTP GET request to the CNB's daily exchange rate XML endpoint.
• Handling potential network or HTTP errors.
• Parsing the XML response to extract relevant exchange rate data.
• Iterating through the rates and printing them in a readable format.

For JSON-formatted data, the URL typically includes /json/ in the path, and the json module in Python would be used for parsing instead of xml.etree.ElementTree.

Community libraries

While the Czech National Bank does not offer official SDKs, the developer community has created various libraries to facilitate interaction with its exchange rate web services. These libraries often wrap the HTTP requests and XML/JSON parsing logic, providing a more convenient interface for developers.

Community contributions typically focus on popular programming languages such as Python, JavaScript (Node.js), and PHP, reflecting the broader developer ecosystem's needs. These libraries can simplify tasks like:

• Fetching daily exchange rates.
• Retrieving historical exchange rates for specific dates.
• Filtering rates by currency code.
• Handling different output formats (XML/JSON).

It is important for developers to evaluate community libraries based on their maintenance status, documentation quality, and active community support. Platforms like GitHub and package managers (e.g., PyPI for Python, npm for JavaScript, Packagist for PHP) are primary sources for discovering and assessing these tools. Developers should verify the source and reliability of any third-party library before integrating it into production systems.

Because the CNB's API is public and does not require authentication, the complexity of these community libraries is generally lower than those for authenticated APIs. They primarily focus on data retrieval and parsing efficiency. For a broader understanding of how community-driven open-source projects contribute to API ecosystems, one can refer to resources discussing Google's approach to open source development.

Developers contributing to or using these libraries play a role in maintaining accessible methods for integrating official financial data into various applications. The ongoing development of such tools ensures that even without official SDKs, the CNB's data remains widely usable across different technical environments.

Below is a conceptual table outlining potential community library characteristics. As specific official SDKs are absent, this table represents a generalized view of what community contributions might offer: