The McClellan Oscillator is a market breadth indicator derived from the difference between the 19-day and 39-day exponential moving averages of the net advances and declines of stocks. It helps traders identify potential trend reversals and market momentum.

Breadth indicators measure market sentiment by comparing advancing and declining stocks. To access them, use platforms like TradingView or MarketSmith. Look for the "Market Breadth" section or apply indicators like Advance/Decline Line (A/D) or McClellan Oscillator.