WIBOR 3-Month Historical Data API: Timeseries, Charts & Downloads
The WIBOR 3-Month (Warsaw Interbank Offered Rate) is a crucial benchmark for interest rates in Poland, reflecting the average rate at which banks lend to one another. For developers building fintech applications, economists, quantitative analysts, and financial data engineers, having access to reliable and comprehensive interest rate data is essential. The Interest Rates API provides a robust solution for retrieving historical data, performing time series analysis, and generating visualizations. This blog post will explore the capabilities of the Interest Rates API, focusing on the WIBOR 3-Month data, and provide practical examples of how to leverage this API effectively.
Understanding the Importance of WIBOR 3-Month Data
The WIBOR 3-Month rate is significant for various financial applications, including loan pricing, risk management, and economic forecasting. By utilizing the Interest Rates API, developers can access historical data, analyze trends, and create visual representations of interest rate movements. This data is vital for making informed decisions in financial markets and for developing applications that require accurate interest rate information.
API Overview and Authentication
The Interest Rates API is designed to provide seamless access to various interest rate data, including central bank rates, interbank rates, and treasury rates. The API uses a simple GET method for all requests, ensuring ease of integration into applications. Authentication is handled through the api_key query parameter, which must be appended to each request URL.
Base URL: https://interestratesapi.com/api/v1/
Key Endpoints for WIBOR 3-Month Data
The Interest Rates API offers several endpoints that are particularly useful for accessing WIBOR 3-Month data. Below, we will discuss each endpoint in detail, including its purpose, request format, and example responses.
1. Retrieve Available Symbols
The first step in using the API is to retrieve the available symbols, including WIBOR 3-Month. This can be done using the /api/v1/symbols endpoint.
cURL Example:
curl "https://interestratesapi.com/api/v1/symbols?category=interbank&api_key=YOUR_KEY"
JSON Response Example:
{
"success": true,
"count": 1,
"symbols": [
{
"symbol": "WIBOR_3M",
"name": "WIBOR 3-Month",
"category": "interbank",
"country_code": "PL",
"currency_code": "PLN",
"frequency": "monthly",
"description": "The average interest rate at which banks lend to each other for a 3-month period."
}
]
}
This endpoint provides a comprehensive list of available symbols, allowing developers to confirm the existence of WIBOR 3-Month and other relevant rates.
2. Fetch Latest Rates
To obtain the most recent WIBOR 3-Month rate, developers can use the /api/v1/latest endpoint. This endpoint returns the latest value for specified symbols.
cURL Example:
curl "https://interestratesapi.com/api/v1/latest?symbols=WIBOR_3M&api_key=YOUR_KEY"
JSON Response Example:
{
"success": true,
"date": "2026-07-02",
"base": "MIXED",
"rates": {
"WIBOR_3M": 5.33
},
"dates": {
"WIBOR_3M": "2026-07-02"
},
"currencies": {
"WIBOR_3M": "PLN"
}
}
This response provides the latest WIBOR 3-Month rate, which is essential for real-time financial applications.
3. Historical Data Retrieval
For point-in-time lookups, the /api/v1/historical endpoint allows users to fetch the WIBOR 3-Month rate for a specific date.
cURL Example:
curl "https://interestratesapi.com/api/v1/historical?date=2025-06-15&symbols=WIBOR_3M&api_key=YOUR_KEY"
JSON Response Example:
{
"success": true,
"date": "2025-06-15",
"base": "PLN",
"rates": {
"WIBOR_3M": 5.33
},
"currencies": {
"WIBOR_3M": "PLN"
}
}
This endpoint is particularly useful for analyzing historical trends and making comparisons over time.
4. Time Series Data
The /api/v1/timeseries endpoint is invaluable for fetching a series of WIBOR 3-Month rates over a specified date range. This is essential for time series analysis and trend identification.
cURL Example:
curl "https://interestratesapi.com/api/v1/timeseries?start=2025-07-02&end=2026-07-02&symbols=WIBOR_3M&api_key=YOUR_KEY"
JSON Response Example:
{
"success": true,
"base": "PLN",
"start_date": "2025-07-02",
"end_date": "2026-07-02",
"rates": {
"WIBOR_3M": {
"2025-07-02": 5.50,
"2025-07-03": 5.45,
"2025-07-04": 5.40
}
},
"frequencies": {
"WIBOR_3M": "daily"
},
"currencies": {
"WIBOR_3M": "PLN"
}
}
This endpoint allows developers to analyze trends over time, making it easier to visualize changes in the WIBOR 3-Month rate.
5. Fluctuation Analysis
The /api/v1/fluctuation endpoint provides statistics on the changes in the WIBOR 3-Month rate over a specified date range. This is useful for understanding volatility and making informed decisions.
cURL Example:
curl "https://interestratesapi.com/api/v1/fluctuation?start=2025-07-02&end=2026-07-02&symbols=WIBOR_3M&api_key=YOUR_KEY"
JSON Response Example:
{
"success": true,
"rates": {
"WIBOR_3M": {
"start_date": "2025-07-02",
"end_date": "2026-07-02",
"start_value": 5.50,
"end_value": 5.33,
"change": -0.17,
"change_pct": -3.09,
"high": 5.50,
"low": 5.25
}
}
}
This data is crucial for risk assessment and financial modeling, allowing analysts to gauge the stability of the WIBOR 3-Month rate.
6. OHLC Data for Charting
The /api/v1/ohlc endpoint provides Open-High-Low-Close (OHLC) data, which is essential for creating candlestick charts. This visualization helps in understanding market trends and price movements.
cURL Example:
curl "https://interestratesapi.com/api/v1/ohlc?symbols=WIBOR_3M&period=monthly&start=2025-07-02&end=2026-07-02&api_key=YOUR_KEY"
JSON Response Example:
{
"success": true,
"period": "monthly",
"start_date": "2025-07-02",
"end_date": "2026-07-02",
"rates": {
"WIBOR_3M": [
{
"period": "2025-07",
"open": 5.50,
"high": 5.55,
"low": 5.45,
"close": 5.33,
"data_points": 30
}
]
}
}
Using this data, developers can create visualizations using libraries like Chart.js or Plotly to represent the WIBOR 3-Month rate effectively.
Building a Data Pipeline with Python
To demonstrate the practical application of the Interest Rates API, we can build a simple data pipeline in Python that fetches WIBOR 3-Month data, processes it using Pandas, and exports it to CSV or Parquet format.
Here’s a complete example:
import requests
import pandas as pd
# Fetching time series data
response = requests.get(
'https://interestratesapi.com/api/v1/timeseries',
params=dict(start='2025-07-02', end='2026-07-02', symbols='WIBOR_3M', api_key='YOUR_KEY')
)
data = response.json()
# Processing the data
dates = data['rates']['WIBOR_3M']
df = pd.DataFrame(list(dates.items()), columns=['Date', 'Rate'])
df['Date'] = pd.to_datetime(df['Date'])
# Exporting to CSV
df.to_csv('wibor_3m_data.csv', index=False)
# Exporting to Parquet
df.to_parquet('wibor_3m_data.parquet', index=False)
This pipeline fetches the WIBOR 3-Month time series data, processes it into a Pandas DataFrame, and exports it in both CSV and Parquet formats for further analysis.
Common Pitfalls in Time Series Analysis
When working with time series data, developers should be aware of several common pitfalls:
- Missing Dates: Ensure that the data covers all required dates, especially when dealing with monthly symbols.
- Frequency Considerations: Understand the frequency of the data (daily vs. monthly) and how it impacts analysis.
- Data Points Interpretation: Be cautious of the
data_pointsfield in the OHLC response, as it indicates the number of data points used to calculate the OHLC values.
Conclusion
The Interest Rates API provides a powerful tool for accessing and analyzing WIBOR 3-Month data. By leveraging the various endpoints, developers can retrieve historical data, perform time series analysis, and create visualizations that enhance their financial applications. Whether you are building a loan pricing model, conducting economic research, or developing a financial dashboard, the Interest Rates API is an invaluable resource.
To get started with the Interest Rates API, visit Try Interest Rates API and explore the features available for your financial data needs. For further information, check out Explore Interest Rates API features and learn how to integrate this powerful tool into your applications.
By utilizing the capabilities of the Interest Rates API, you can streamline your data retrieval processes and focus on building innovative financial solutions.




