McClellan Oscillator
Calculate the McClellan Oscillator for a given price series.
The McClellan Oscillator is a breadth indicator that measures the difference between the exponential moving average of advancing stocks and the exponential moving average of declining stocks.
The formula is as follows:
\[\text{McClellan Oscillator} = \operatorname{EMA}(\text{Advancers}) - \operatorname{EMA}(\text{Decliners})\]Also known as: McClellan oscillator, market breadth.
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Calculate the McClellan Oscillator in Python
The McClellan Oscillator is available in the Technicals module of the open-source Finance Toolkit. Install it with:
pip install financetoolkit -U
Then call get_mcclellan_oscillator as shown below.
from financetoolkit import Toolkit
toolkit = Toolkit(tickers=["AAPL", "MSFT"])
toolkit.technicals.get_mcclellan_oscillator()
Which returns:
| Date | AAPL | MSFT | Benchmark |
|---|---|---|---|
| 2026-06-18 | 5.1473 | -4.4405 | 9.1566 |
| 2026-06-22 | 4.8047 | -6.079 | 8.7467 |
| 2026-06-23 | 4.3522 | -7.1196 | 7.8119 |
| 2026-06-24 | 3.8826 | -8.3976 | 6.9567 |
| 2026-06-25 | 2.5652 | -10.0799 | 6.2436 |
| 2026-06-26 | 1.8575 | -10.4608 | 5.3373 |
| 2026-06-29 | 1.1411 | -10.9542 | 5.1361 |
| 2026-06-30 | 0.9039 | -11.0988 | 5.227 |
| 2026-07-01 | 0.9476 | -10.6039 | 5.228 |
| 2026-07-02 | 1.6926 | -9.8173 | 5.1538 |
Parameters
get_mcclellan_oscillator accepts the following parameters:
- period (str, optional): The time period to consider for historical data. Can be “daily”, “weekly”, “quarterly”, or “yearly”. Defaults to “daily”.
- close_column (str, optional): The name of the column containing the close prices. Defaults to “Adj Close”.
- short_ema_window (int, optional): The window size for the short-term EMA. Defaults to 19.
- long_ema_window (int, optional): The window size for the long-term EMA. Defaults to 39.
- rounding (int | None, optional): The number of decimals to round the results to. Defaults to 4.
- growth (bool, optional): Whether to calculate the growth of the indicator values. Defaults to False.
- lag (int | list[int], optional): The lag to use for the growth calculation.
- standardize (bool, optional): Whether to standardize (Z-Score) the result. When combined with growth=True, standardizes the growth values instead of the raw values. Defaults to False. Defaults to 1.
Related Breadth Indicators
The Technicals module page introduces the module, and the sidebar lists all of its functions.